Supporting Information Iminophenyl Oxazolinylphenylamine for Enantioselective Cobalt-catalyzed Hydrosilylation of Aryl Ketones

Transcript

1 Supporting Information Iminophenyl Oxazolinylphenylamine for Enantioselective Cobalt-catalyzed Hydrosilylation of Aryl Ketones Xu Chen and Zhan Lu* Department of Chemistry, Zhejiang University, 866 Yuhangtang Road, Hangzhou , China I. Genera Information...S1 II. III. IV. Procedures for Preparation of Ligands....S1 Highly Enantioselective Hydrosilylation of Aryl Ketones..S9 References.S23 V. NMR Spectra S24 VI. HPLC Spectra......S79 I. General Information Ether, tetrahydrofuran, 1,4-dioxane and toluene were distilled from sodium benzophenoneketyl prior to use and dichloromethane was distilled from CaH 2. Triethoxysilane ((EtO) 3 SiH) and other silanes were purchased from Tokyo Chemical Industry Co.. Sodium triethylborohydride solution (1.0 M in THF) was purchased from Sigma-Aldrich Co.. The other commercial available chemicals were used as received. NMR spectra were recorded on a Bruker-400 instrument. 1 H NMR chemical shifts were referenced to tetramethylsilane signal (0 ppm), 13 C NMR chemical shifts were referenced to the solvent resonance (77.00 ppm, CDCl 3 ). The following abbreviations (or combinations thereof) were used to explain multiplicities: s = singlet, d = doublet, t = triplet, q = quadruplet, m = multiplet, br = broad. IR spectra were recorded on a Perkin-Elmer Spectrum One FTIR spectrometer with diamond ATR accessory. HPLC analyses were performed on a Shimadzu SPD-20A. High-resolution mass spectra (HRMS) were recorded on EI-TOF (electrospray ionization-time of flight). II. Procedures for Preparation of Ligands. S1a-S1e were prepared according to the literature. [1] S1

2 (S)-(+)-2-(4-phenyl-4,5-dihydrooxazol-2-yl)aniline (S1a). 80% yield, white solid. Optical Rotation: [ ] 20 D = (c 1.04, CHCl 3 ) (lit. [2] : [ ] 20 D = (c 1.0, CHCl 3 )); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), (m, 6H), (m, 2H), 6.13 (brs, 2H), (m, 1H), 4.68 (dd, J = 10.0, 8.4 Hz, 1H), 4.12 (t, J = 8.4 Hz, 1H). All the spectroscopic data were in agreement with the reported ones. [2] (S)-(+)-2-(4-benzyl-4,5-dihydrooxazol-2-yl)aniline (S1b). 69% yield, white solid. Optical Rotation: [ ] 20 D = (c 1.03, CHCl 3 ) (lit. [2] : [ ] 20 D = (c 1.0, CHCl 3 )); 1 H NMR (400 MHz, CDCl 3 ): δ 7.67 (d, J = 8.0 Hz, 1H), (m, 2H), (m, 4H), (m, 2H), 6.09 (brs, 2H), (m, 1H), (m, 1H), 4.02 (dd, J = 8.0, 7.6 Hz, 1H), 3.13 (dd, J = 13.6, 6.0 Hz, 1H), 2.76 (dd, J = 13.6, 8.0 Hz, 1H). All the spectroscopic data were in agreement with the reported ones. [2] 2-((3aS, 8aR)-(+)-8, 8a-dihydro-3aH-indeno[1,2-d]oxazol-2-yl)aniline (S1c). 68% yield, white solid. Optical Rotation: [ ] 20 D = (c 0.95, CHCl 3 ) (lit. [3] : [ ] 20 D = (c 1.0, CH 2 Cl 2 )); 1 H NMR (400 MHz, CDCl 3 ): δ 7.67 (d, J = 8.0 Hz, 1H), (m, 1H), (m, 3H), 7.15 (t, J = 7.6 Hz, 1H), (m, 2H), 6.05 (brs, 2H), 5.77 (d, J = 8.0 Hz, 1H), 5.36 (t, J = 7.2 Hz, 1H), 3.48 (dd, J = 17.6, 6.4 Hz, 1H), 3.34 (d, J = 17.6 Hz, 1H). All the spectroscopic data were in agreement with the reported ones. [3] (S)-(+)-2-(4-isopropyl-4,5-dihydrooxazol-2-yl)aniline (S1d). 88% yield, white solid. Optical Rotation: [ ] 20 D = (c 0.99, EtOH) (lit. [2] : [ ] 20 D = (c 1.0, EtOH)), 1 H NMR (400 MHz, CDCl 3 ): δ 7.67 (d, J = 8.0 Hz, 1H), (m, 1H), (m, 2H), 6.13 (brs, 2H), (m, 1H), (m, 1H), 4.00 (t, J = 8.0 Hz, 1H), (m, 1H), 1.03 (d, J = 6.8 Hz, 3H), 0.94 (d, J = 6.8 Hz, 3H). All the spectroscopic data were in agreement with the reported ones. [2] S2

3 (S)-(+)-2-(4-(tert-butyl)-4,5-dihydrooxazol-2-yl)aniline (S1e). 63% yield, white solid. Optical Rotation: [ ] 20 D = (c 0.95, EtOH) (lit. [2] : [ ] 20 D = (c 1.0, EtOH)), 1 H NMR (400 MHz, CDCl 3 ): δ 7.67 (d, J = 7.6 Hz, 1H), 7.19 (t, J = 7.6 Hz, 1H), (m, 2H), 6.14 (brs, 2H), (m, 1H), (m, 2H), 0.94 (s, 9H). All the spectroscopic data were in agreement with the reported ones. [2] (S)-(+)-2-((2-(4-phenyl-4,5-dihydrooxazol-2-yl)phenyl)amino)benzald ehyde (S2a). Prepared according to a previously reported procedure with a slight modification, [1a] a 100 ml flame-dried Schlenk flask was washed with nitrogen three times and charged with Pd(dba) 2 ( g, 0.1 mmol), Xantphos ( g, 0.2 mmol), S1a ( g, 2.4 mmol), 2-bromobenzaldehyde ( g, 2 mmol, 1.0 equiv.) and K 2 CO 3 ( g, 10 mmol). Then, the flask was evacuated and backfilled with nitrogen. Dioxane (10 ml) was added by syringe. The mixture was refluxed for 32 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent to afford the title compound ( g, 83% yield) as a yellow oil. IR (neat): 3233, 3027, 2741, 1680, 1635, 1582, 1521, 1451 cm -1 ; Optical Rotation: [α] 20 D = (c 1.06, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), (s, 1H), 7.93 (d, J = 7.6 Hz, 1H), 7.70 (d, J = 7.6 Hz, 1H), (m, 3H), (m, 5H), (m, 1H), 7.00 (dt, J = 20.0, 7.6 Hz, 2H), 5.52 (t, J = 9.2 Hz, 1H), 4.76 (t, J = 9.2 Hz, 1H), (m, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 191.9, 164.0, 144.5, 143.0, 142.2, 134.7, 134.1, 131.7, 130.6, 128.7, 127.4, 126.5, 125.0, 120.6, 120.3, 118.6, 117.7, 114.8, 73.4, 70.1; HRMS (EI) calculated for [C 22 H 18 N 2 O 2 ] + requires m/z , found m/z (S)-(+)-2-((2-(4-benzyl-4,5-dihydrooxazol-2-yl)phenyl)amino)benzalde hyde (S2b). Prepared according to a previously reported procedure with a slight modification, [1a] a 100 ml flame-dried Schlenk flask was washed with nitrogen three times and charged with Pd(dba) 2 ( g, 0.48 mmol), Xantphos ( g, 6.0mmol), S1b ( g, 11 mmol), 2-bromobenzaldehyde S3

4 ( g, 10.1 mmol) and K 2 CO 3 ( g, 20 mmol). Then, the flask was evacuated and backfilled with nitrogen. Dioxane (20 ml) was added by syringe. The mixture was refluxed for 12 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent to afford the title compound ( g, 78% yield) as a yellow oil. IR (neat): 3242, 3026, 2739, 1680, 1637, 1583, 1522, 1452 cm -1 ; Optical Rotation: [α] 20 D = (c 0.88, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), (s, 1H), 7.81 (d, J = 7.6 Hz, 1H), 7.68 (d, J = 7.6 Hz, 1H), 7.48 (dd, J = 18.8, 8.4 Hz, 2H), (m, 1H), (m, 1H), (m, 5H), 6.98 (t, J = 7.2 Hz, 1H), 6.90 (t, J = 7.2 Hz, 1H), (m, 1H), 4.26 (t, J = 8.8 Hz, 1H), 4.04 (t, J = 8.0 Hz, 1H), 3.18 (dd, J = 14.0, 5.6 Hz, 1H), 2.78 (dd, J = 13.6, 8.0 Hz, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 191.2, 162.5, 143.9, 142.3, 137.5, 134.3, 133.9, 131.1, 129.9, 128.9, 128.0, 126.0, 124.3, 120.0, 119.8, 117.6, 117.1, 114.4, 70.1, 67.6, 41.2; HRMS (EI) calculated for [C 23 H 20 N 2 O 2 ] + requires m/z , found m/z ((2-((3aS,8aR)-(+)-8,8a-dihydro-3aH-indeno[1,2-d]oxazol-2-yl)phe nyl)amino)benzaldehyde (S2c). Prepared according to a previously reported procedure with a slight modification, [1a] a 100 ml flame-dried Schlenk flask was washed with nitrogen three times and charged with Pd(dba) 2 ( g, 0.48 mmol), Xantphos ( g, 6.1 mmol), S1c ( g, 11 mmol), 2-bromobenzaldehyde (1.8967g, 10.3 mmol) and K 2 CO 3 ( g, 20.0 mmol). Then, the flask was evacuated and backfilled with nitrogen. Dioxane (20 ml) was added by syringe. The mixture was refluxed for 12 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent to afford the title compound ( g, 85% yield) as a yellow oil. IR (neat): 3229, 3026, 2738, 1679, 1632, 1582, 1521, 1402 cm -1 ; Optical Rotation: [α] 20 D = (c 1.06, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), (s, 1H), 7.84 (dd, J = 8.0, 1.6 Hz, 1H), 7.70 (dd, J = 7.6, 1.6 Hz, 1H), 7.60 (d, J = 7.2 Hz, 1H), 7.48 ( t, J = 9.2 Hz, 2H), (m, 1H), (m, 4H), (m, 1H), (m, 1H), 5.82 (d, J = 7.6 Hz, 1H), (m, 1H), 3.49 (dd, J = 18.0, 6.4 Hz, 1H), 3.37 (d, J = 17.6 Hz, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 192.0, 163.2, 144.4, 142.4, 142.0, 139.5, 134.7, 134.4, 131.4, S4

5 130.4, 128.4, 127.5, 125.8, 125.1, 124.4, 120.3, 120.1, 117.7, 117.6, 115.1, 82.0, 76.95, 39.6; HRMS (EI) calculated for [C 23 H 18 N 2 O 2 ] + requires m/z , found m/z (S)-(+)-2-((2-(4-isopropyl-4,5-dihydrooxazol-2-yl)phenyl)amino)benza ldehyde (S2d). Prepared according to a previously reported procedure with a slight modification, [1a] a 100 ml flame-dried Schlenk flask was washed with nitrogen three times and charged with Pd(dba) 2 ( g, 0.48 mmol), Xantphos ( g, 0.6 mmol), S1d ( g, 11 mmol), 2-bromobenzaldehyde ( g, 10.1 mmol, 1.0 equiv.) and K 2 CO 3 ( g, 19.8 mmol). Then, the flask was evacuated and backfilled with nitrogen. Dioxane (20 ml) was added by syringe. The mixture was refluxed for 12 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent to afford the title compound ( g, 85% yield) as a yellow oil. IR (neat): 3229, 2959, 2737, 1682, 1639, 1583, 1522, 1452, 1317 cm -1 ; Optical Rotation: [α] 20 D = (c 0.92, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), (s, 1H), 7.85 (d, J = 8.0 Hz, 1H), 7.71 (d, J = 7.6 Hz, 1H), (m, 2H), 7.42 (t, J = 7.6 Hz, 1H), (m, 1H), 7.01 (t, J = 7.6 Hz, 1H), 6.94 (t, J = 7.6 Hz, 1H), 4.37 (t, J = 8.4 Hz, 1H), (m, 1H), 4.05 (t, J = 8.0 Hz, 1H), (m, 1H), 1.04 (d, J = 6.8 Hz, 3H), 0.95 (d, J = 6.4 Hz, 3H); 13 C NMR (101 MHz, CDCl 3 ) δ 191.8, 162.5, 144.6, 142.6, 134.7, 134.3, 131.3, 130.3, 124.7, 120.3, 120.2, 118.1, 117.5, 115.1, 73.2, 69.3, 33.1, 18.8, 18.6; HRMS (EI) calculated for [C 19 H 20 N 2 O 2 ] + requires m/z , found m/z (S)-(+)-2-((2-(4-(tert-butyl)-4,5-dihydrooxazol-2-yl)phenyl)amino)ben zaldehyde (S2e). Prepared according to a previously reported procedure with a slight modification, [1a] a 100 ml flame-dried Schlenk flask was washed with nitrogen three times and charged with Pd(dba) 2 ( g, 0.85 mmol), Xantphos ( g, 1.7 mmol), S1e ( g, 18 mmol), 2-bromobenzaldehyde (3.1254g, 17 mmol) and K 2 CO 3 ( g, 34 mmol). Then, the flask was evacuated and backfilled with nitrogen. Dioxane (34 ml) was added by syringe. The mixture was refluxed for 12 h. After cooling to room temperature, the mixture was filtered and washed with S5

6 EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent to afford the title compound ( g, 78% yield) as a yellow solid. M.p o C; IR (neat): 3230, 2955, 2735, 1682, 1640, 1583, 1521, 1452 cm -1 ; Optical Rotation: [α] 20 D = (c 1.04, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), (s, 1H), 7.85 (d, J = 8.0 Hz, 1H), 7.71 (d, J = 8.0 Hz, 1H), 7.52 (dd, J = 18.0, 8.0 Hz, 2H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), 4.30 (t, J = 12.4 Hz, 1H), 4.15 (dd, J = 12.4, 8.0 Hz, 2H), 0.95 (s, 9H); 13 C NMR (101 MHz, CDCl 3 ) δ 191.7, 162.5, 144.6, 142.7, 134.7, 134.2, 131.3, 130.2, 124.7, 120.4, 120.2, 118.3, 117.5, 115.1, 76.6, 67.4, 33.9, 25.9; HRMS (EI) calculated for [C 20 H 22 N 2 O 2 ] + requires m/z , found m/z (S,E)-(+)-2,6-diisopropyl-N-(2-((2-(4-phenyl-4,5-dihydrooxazol-2- yl)phenyl)amino)benzylidene)aniline (La). A 100 ml flame-dried Schlenk flask was charged with 4 Å molecular sieves (4.88 g), 2, 6-diisopropylaniline (4.0 ml, 0.94 g/ml, 21.3 mmol), S2a ( g, 15.5 mmol), p-toluenesulfonic acid monohydrate ( g, 1.3 mmol). Then, the flask was evacuated and backfilled with nitrogen. Toluene (30 ml) was added and the mixture was refluxed for 72 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent and then crystallized from ethanol to afford the title compound ( g, 76% yield) as a light yellow solid. M.p o C; IR (neat): 3207, 2961, 1631, 1583, 1516, 1456, 1268 cm -1 ; Optical Rotation: [α] 20 D = (c 1.00, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), 8.40 (s, 1H), 8.05 (d, J = 7.6 Hz, 1H), 7.85 (d, J = 7.6 Hz, 1H), 7.45 (d, J = 4.0 Hz, 2H), (m, 3H), (m, 4H), (m, 4H), 6.80 (t, J = 7.5 Hz, 1H), 5.33 (dd, J = 9.6, 8.4 Hz, 1H), 4.63 (dd, J = 9.6, 8.8 Hz, 1H), 4.08 (t, J = 8.0 Hz, 1H), (m, 2H), 1.04 (d, J = 6.8 Hz, 6H), 0.98 (d, J = 6.8 Hz, 6H); 13 C NMR (101 MHz, CDCl 3 ) δ 164.7, 160.5, 149.5, 146.3, 142.2, 137.6, 132.2, 131.9, 130.3, 129.7, 129.3, 128.5, 127.3, 126.3, 124.3, 123.9, 123.8, 122.8, 117.9, 114.8, 111.5, 73.3, 69.9, 27.8, 23.4, 23.3; HRMS (EI) calculated for [C 34 H 35 N 3 O] + requires m/z , found m/z S6

7 (S,E)-(+)-N-(2-((2-(4-benzyl-4,5-dihydrooxazol-2-yl)phenyl)amino )benzylidene)-2,6-diisopropylaniline (Lb). A 100 ml flame-dried Schlenk flask was charged with 4 Å molecular sieves ( g), 2, 6-diisopropylaniline (1.4 ml, 0.94 g/ml, 0.94 g/ml, 7.54 mmol), S2b ( g, 5.8 mmol), p-toluenesulfonic acid monohydrate ( g, 0.53 mmol). Then, the flask was evacuated and backfilled with nitrogen. Toluene (12 ml) was added and the mixture was refluxed for 72 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent and then crystallized from ethanol to afford the title compound ( g, 67% yield) as a light yellow solid. M.p o C; IR (neat): 2962, 1632, 1583, 1517, 1457, 1054 cm -1 ; Optical Rotation: [α] 20 D = (c 1.12, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), 8.44 (s, 1H), 8.06 (d, J = 8.0 Hz, 1H), 7.75 (d, J = 8.0 Hz, 1H), (m, 2H), (m, 5H), (m, 6H), (m, 1H), (m, 1H), 4.16 (t, J = 8.8 Hz, 1H), 3.98 (dd, J = 8.4, 7.2 Hz, 1H), (m, 3H), 2.51 (dd, J = 13.6, 9.2 Hz, 1H), (m, 12H); 13 C NMR (101 MHz, CDCl 3 ) δ 163.7, 160.7, 149.5, 146.0, 142.5, 137.9, 137.6, , , 130.1, 129.9, 129.1, 129.0, 128.4, 126.4, 124.0, 123.8, 123.5, 122.9, 118.0, 114.8, 112.0, 70.3, 67.8, 41.7, 27.9, 23.5, 23.4; HRMS (EI) calculated for [C 35 H 37 N 3 O] + requires m/z , found m/z (E)-(+)-N-(2-((2-((3aS,8aR)-8,8a-dihydro-3aH-indeno[1,2-d]oxaz ol-2-yl)phenyl)amino)benzylidene)-2,6-diisopropylaniline (Lc). A 100 ml flame-dried Schlenk flask was charged with 4 Å molecular sieves ( g), 2, 6-diisopropylaniline (1.20 ml, 0.94 g/ml, 6.4 mmol), S2c ( g, 5.0 mmol), p-toluenesulfonic acid monohydrate ( g, 0.44 mmol). Then, the flask was evacuated and backfilled with nitrogen. Toluene (10 ml) was added and the mixture was refluxed for 72 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent and then crystallized from ethanol to afford the title compound ( g, 66% yield) as a light yellow solid. M.p o C; IR (neat): 3167, 2960, 1627, 1583, 1515, 1458, 1054 S7

8 cm -1 ; Optical Rotation: [α] 20 D = (c 0.98, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), 8.50 (s, 1H), 8.02 (d, J = 7.6 Hz, 1H), 7.76 (d, J = 7.6 Hz, 1H), 7.49 (d, J = 8.4 Hz, 1H), (m, 1H), 7.21 (d, J = 3.6 Hz, 2H), (m, 6H), 6.93 (m, 1H), 6.83 (d, J = 7.6 Hz, 1H), (m, 1H), 5.60 (d, J = 7.6 Hz, 1H), 5.28 (t, J = 7.2 Hz, 1H), (m, 2H), (m, 2H), 1.12 (d, J = 6.8 Hz, 6H), 1.10 (d, J = 6.8 Hz, 6H); 13 C NMR (101 MHz, CDCl 3 ) δ 163.8, 160.6, 149.7, 145.1, 142.5, 141.9, 139.4, 137.7, 131.7, 130.2, 130.1, 128.2, 127.6, 127.5, 125.5, 125.0, 124.1, 123.0, 122.7, 122.2, 118.2, 115.2, 112.6, 81.7, 39.4, 27.9, 23.4, 23.4; HRMS (EI) calculated for [C 35 H 35 N 3 O] + requires m/z , found m/z (S,E)-(+)-2,6-diisopropyl-N-(2-((2-(4-isopropyl-4,5-dihydrooxazol- 2-yl)phenyl)amino)benzylidene)aniline (Ld). A 100 ml flame-dried Schlenk flask was charged with 4 Å molecular sieves ( g), 2, 6- diisopropylaniline (1.25 ml, 0.94 g/ml, 6.5 mmol), S2d ( g, 5.0 mmol), p-toluenesulfonic acid monohydrate ( g, 0.23 mmol). Then, the flask was evacuated and backfilled with nitrogen. Toluene (10 ml) was added and the mixture was refluxed for 72 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent and then crystallized from ethanol to afford the title compound ( g, 57% yield) as a light yellow solid. M.p o C; IR (neat): 3158, 2960, 1632, 1585, 1516, 1458, 1054 cm -1 ; Optical Rotation: [α] 20 D = (c 0.98, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), 8.45 (s, 1H), 8.13 (d, J = 7.5 Hz, 1H), 7.75 (dd, J = 8.0, 1.2 Hz, 1H), (m, 2H), (m, 2H), (m, 4H), (m, 1H), (m, 1H), (m, 2H), (m, 2H), (m, 1H), 1.09 (t, J = 6.4 Hz, 12H), 0.84 (d, J = 6.8 Hz, 3H), 0.75 (d, J = 6.8 Hz, 3H); 13 C NMR (101 MHz, CDCl 3 ) δ 163.3, 160.3, 149.5, 146.3, 142.4, 137.6, 131.9, 131.8, 130.0, 129.6, 129.3, 124.5, , , 122.8, 117.7, 114.4, 111.7, 72.5, 68.5, 32.6, 27.8, 23.5, 23.4, 18.9, 17.8; HRMS (EI) calculated for [C 31 H 37 N 3 O] + requires m/z , found m/z S8

9 (S,E)-(+)-N-(2-((2-(4-(tert-butyl)-4,5-dihydrooxazol-2-yl)phenyl)a mino)benzylidene)-2,6-diisopropylaniline (Le). A 100 ml flame-dried Schlenk flask was charged with 4 Å molecular sieves ( g), 2, 6-diisopropylaniline (1.25 ml, 0.94 g/ml, 6.5 mmol), S2e ( g, 5.0 mmol), p-toluenesulfonic acid monohydrate ( g, 0.24 mmol). Then, the flask was evacuated and backfilled with nitrogen. Toluene (10 ml) was added and the mixture was refluxed for 72 h. After cooling to room temperature, the mixture was filtered and washed with EtOAc. The combined filtrate were concentrated and purified by column chromatography using PE/EA = 20:1 as the eluent and then crystallized from ethanol to afford the title compound ( g, 71% yield) as a light yellow oil. IR (neat): 3166, 2960, 1632, 1585, 1515, 1457, 1051 cm -1 ; Optical Rotation: [α] 20 D = (c 0.84, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ): δ (s, 1H), 8.46 (s, 1H), 8.17 (dd, J = 8.0, 1.2 Hz, 1H), 7.75 (dd, J = 8.0, 1.6 Hz, 1H), (m, 1H), 7.39 (d, J = 7.6 Hz, 1H), 7.27 (t, J = 7.6 Hz, 1H), (m, 1H), (m, 3H), 6.93 (d, J = 8.0 Hz, 1H), (m, 1H), 4.19 (dd, J = 10.0, 8.8 Hz, 1H), (m, 1H), 3.99 (dd, J = 10.0, 7.6 Hz, 1H), (m, 2H), 1.08 (t, J = 6.8 Hz, 12H), 0.79 (s, 9H); 13 C NMR (101 MHz, CDCl 3 ) δ 163.4, 160.2, 149.5, 146.7, 142.3, 137.6, 132.0, 131.9, 130.3, 129.9, 129.0, 125.2, 124.3, 123.9, 122.8, 117.5, 114.1, 111.4, 76.1, 67.1, 33.7, 27.8, 25.7, 23.5, 23.4; HRMS (EI) calculated for [C 32 H 39 N 3 O] + requires m/z , found m/z III. Highly Enantioselective Hydrosilylation of Ketones General Procedures for Hydrosilylation of Ketones: To a 25 ml flame-dried Schlenk flask cooled under nitrogen, La (0.008 mmol), DCM (1 ml), CoCl 2 (50 μl, 0.1 M in THF) were added. The mixture was stirred at room temperature for 2 h. Then, NaBHEt 3 (5 μl, 1 M in THF), (EtO) 3 SiH (369 μl, 2.0 mmol), ketone (1.0 mmol) were added in sequence and stirred at room temperature for 15 h and quenched with K 2 CO 3 /MeOH (saturated). After stirring for 2 h at room temperature, the crude mixture was evaporated and purified by column chromatography using PE/EA = 20:1 and PE/EA = 10:1 to give the corresponding products. S9

10 Table S1 Optimization studies on different silanes, reductants, solvent. Entry Silane Reductant Solvent Yield (%) [a] Ee (%) [b] Note 1 (EtO) 3 SiH NaBHEt 3 THF CX3042B 2 (EtO) 3 SiH - THF CX3068C 3 (EtO) 3 SiH NaBHEt 3 dioxane CX3057B 4 (EtO) 3 SiH NaHBEt 3 toluene CX3057C 5 (EtO) 3 SiH NaBHEt 3 Et 2 O CX3057D 6 (EtO) 3 SiH NaBHEt 3 MeCN CX3059B 7 (EtO) 3 SiH NaBHEt 3 CHCl CX3059C 8 (EtO) 3 SiH NaBHEt 3 THF CX3062A 9 (EtO) 3 SiH NaBHEt 3 EtOH 0 / CX3062C 10 (EtO) 3 SiH NaBHEt 3 CH 2 Cl CX3062B 11 (EtO) 3 SiH Et 2 Zn CH 2 Cl CX3065A 12 (EtO) 3 SiH LiBHEt 3 CH 2 Cl CX3065B 13 (EtO) 3 SiH N-Selectride CH 2 Cl CX3065C 14 (EtO) 3 SiH EtMgBr CH 2 Cl CX3065D 15 Ph 3 SiH NaBHEt 3 CH 2 Cl 2 10 / CX3069B 16 Et 3 SiH NaBHEt 3 CH 2 Cl 2 5 / CX3069C 17 PMHS NaBHEt 3 CH 2 Cl CX3069D81 [a] yields were determined using TMSPh as an internal standard. [b] ee values were determined by chiral HPLC analysis. (R)-(+)-1-phenylethanol (2a). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), acetophenone (120 μl, 1.02 g/ml, 98%, 1.0 mmol) afforded 2a ( g, 0.84 mmol, 84% yield) as a colorless S10

11 oil. Optical Rotation: [ ] 20 D = (c 0.92, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.0, CHCl 3 ), 98.1% ee), 97.2% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 12.6 (major), 13.4 (minor); 1 H NMR (400 MHz, CDCl 3 ) δ (m, 4H), (m, 1H), (m, 1H), 1.90 (d, J = 3.6 Hz, 1H), 1.49 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(p-tolyl)ethanol (2b). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(p-tolyl)ethanone (137 μl, 1.08 g/ml, 98%, 1.0 mmol) afforded 2b ( g, 0.79 mmol, 79% yield) as a colorless oil. Optical Rotation: [α] 20 D = (c 1.03, CHCl 3 ) (lit. [4] : [α] 20 D = (c 1.01, CHCl 3 ), 98.7% ee), 97.2% ee determined by HPLC, HPLC conditions: Chiralcel AD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 14.8 (major), 15.9 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.26 (d, J = 8.4 Hz, 2H), 7.16 (d, J = 8.0 Hz, 2H), 4.86 (q, J = 6.4 Hz, 1H), 2.34 (s, 3H), 1.86 (s, 1H), 1.48 (d, J = 6.8 Hz, 3H). (R)-(+)-1-(m-tolyl)ethanol (2c). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(m-tolyl) ethanone (155 μl, 0.98 g/ml, 98%, 1.0 mmol) afforded 2c ( g, 0.84 mmol, 84% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.04, CHCl 3 ) ( lit. [4] : [ ] 20 D = (c 0.95,CHCl 3 ), 96% ee), 97.4% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 12.9 (major), 17.1 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), (m, 2H), 7.09 (d, J = 7.6 Hz, 1H), 4.86 (q, J = 6.4 Hz, 1H), 2.36 (s, 3H), 1.86 (s, 1H), 1.48 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(o-tolyl)ethanol (2d). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(2-methyl)ethanone (134 μl, 1.02 g/ml, 98%, 1.0 mmol) afforded 2d ( g, 0.80 mmol, 80% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.99, CHCl 3 ) ( lit. [5] : [ ] 27 D = (c S11

12 0.96, CHCl 3 ), 98% ee), 99.7% ee determined by HPLC, HPLC conditions: Chiralcel AD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 12.7 (major), 14.6 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.51 (d, J = 7.6 Hz, 1H), (m, 1H), (m, 2H), 5.13 (q, J = 6.4 Hz, 1H), 2.34 (s, 3H), 1.76 (s, 1H), 1.46 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-methoxyphenyl)ethanol (2e). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-methoxyphenyl)ethanone ( g, 98%, 1.0 mmol) afforded 2e ( g, 0.84 mmol, 84% yield) as a colorless oil (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.18, CHCl 3 ) (lit. [6] : [ ] 22 D = (c 0.5, CHCl 3 ), 89% ee), 94.4% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 90/10, 1.0 ml/min, n = 220 nm, tr 14.4 (major), 18.4 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2H), (m, 2H), 4.86 (q, J = 6.4 Hz, 1H), 3.81 (s, 3H), 1.76 (s, 1H), 1.48 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(3-methoxyphenyl)ethanol (2f). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(3-methoxyphenyl)ethanone (145 μl, 1.09 g/ml, 95%, 1.0 mmol) afforded 2f ( g, 0.79 mmol, 79% yield) as a colorless oil (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.01, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.91, CHCl 3 ), 98.3% ee), 97.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 19.9 (major), 20.8 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), (m, 2H), (m, 1H), 4.86 (q, J = 6.4 Hz, 1H), 3.81 (s, 3H), 1.96 (s, 1H), 1.48 (d, J = 6.4 Hz, 3H). `(R)-(+)-1-(2-methoxyphenyl)ethanol (2g). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in S12

13 THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(2-methoxyphenyl)ethanone (142 μl, 1.09 g/ml, 97%, 1.0 mmol) afforded 2g ( g, 0.86 mmol, 86% yield) as a colorless oil (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 0.75, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.93, CHCl 3 ), 91% ee), 97.6% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 16.2 (minor), 17.0 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.34 (d, J = 6.4 Hz, 1H), (m, 1H), 6.96 (t, J = 7.6 Hz, 1H), 6.88 (d, J = 8.0 Hz, 1H), (m, 1H), 3.86 (s, 3H), 2.64 (d, J = 5.2 Hz, 1H), 1.51 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-isobutylphenyl)ethanol (2h). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-isobutylphenyl)ethanone (189 μl, 0.95 g/ml, 98%, 1.0 mmol) afforded 2h ( g, 0.87 mmol, 87% yield) as a colorless oil (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.12, CHCl 3 ) (lit. [4] : [ ] 22 D = (c 1.03, CHCl 3 ), 97.6% ee), 98.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 7.7 (major), 8.4 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.28 (d, J = 8.0 Hz, 2H), 7.13 (d, J = 7.6 Hz, 2H), (m, 1H), 2.47 (d, J = 7.2 Hz, 2H), (m, 1H), 1.73 (d, J = 3.2 Hz, 1H), 1.50 (d, J = 6.4 Hz, 3H), 0.90 (d, J = 6.4 Hz, 6H). (R)-(+)-1-(4-fluorophenyl)ethanol (2i). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-fluorophenyl)ethanone (124 μl, 1.14 g/ml, 98%, 1.0 mmol) afforded 2q ( g, 0.73 mmol, 73% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.12, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.97, CHCl 3 ), 96.7% ee), 93.0% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 15.6 (major), 17.8 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2H), 7.03 (t, J = 8.4 Hz, 2H), 4.89 (q, J = 6.4 Hz, 1H), 1.78 (s, 1H), 1.48 (d, J = 6.4 Hz, 3H). S13

14 (R)-(+)-1-(3-fluorophenyl)ethanol (2j). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(3-fluorophenyl)ethanone (125 μl, 1.13 g/ml, 98%, 1.0 mmol) afforded 2j ( g, 0.80 mmol, 80% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.08, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.18, CHCl 3 ), 95% ee), 95.0% ee determined by HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 16.4 (minor), 17.7 (major); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), (m, 2H), (m, 1H), (m, 1H), 1.93 (s, 1H), 1.49 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(2-fluorophenyl)ethanol (2k). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(2-fluorophenyl)ethanone (125 μl, 1.13 g/ml, 98%, 1.0 mmol) afforded 2k ( g, 0.82 mmol, 82% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.95, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.03, CHCl 3 ), 95.0% ee), 95.0% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 10.6 (major), 11.5 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.48 (td, J = 7.6, 1.2 Hz, 1H), (m, 1H), 7.14 (t, J = 7.6 Hz, 1H), (m, 1H), 5.19 (q, J = 6.4 Hz, 1H), 2.12 (d, J = 24.0 Hz, 1H), 1.50 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-chlorophenyl)ethanol (2l). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-chlorophenyl)ethanone (131 μl, 1.19 g/ml, 99%, 1.0 mmol) afforded 2l ( g, 0.82 mmol, 82% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.99, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.93,CHCl 3 ), 96.1% ee), 96.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 14.4 (major), 15.4 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), (m, 1H), 1.95 (d, J = S14

15 2.8 Hz, 1H), 1.47 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(3-chlorophenyl)ethanol (2m). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(3-chlorophenyl)ethanone (133 μl, 1.19 g/ml, 98%, 1.0 mmol) afforded 2m ( g, 0.84 mmol, 84% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.82, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.92, CHCl 3 ), 97.7% ee), 96.6% ee determined by HPLC, HPLC conditions: Chiralcel AD-H, n-hexane/i-proh = 99/1, 0.7 ml/min, n = 220 nm, tr 38.5 (major), 41.4 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.38 (s, 1H), (m, 3H), (m, 1H), 1.88 (d, J = 2.4 Hz, 1H), 1.48 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(2-chlorophenyl)ethanol (2n). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(2-chlorophenyl)ethanone (133 μl, 1.19 g/ml, 98%, 1.0 mmol) afforded 2n ( g, 0.84 mmol, 84% yield) as a colorless oil. Optical Rotation: [α] 20 D = (c 1.14, CHCl 3 ) (lit. [5] : [α] 26 D = (c 1.91, CHCl 3 ), 99% ee), 97.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 11.3 (major), 12.2 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.59 (dd, J = 7.6, 1.2 Hz, 1H), (m, 2H), 7.20 (td, J = 7.6, 1.6 Hz, 1H), δ (m, 1H), 2.03 (s, 1H), 1.49 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-bromophenyl)ethanol (2o). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-bromophenyl)ethanone ( g, 98%, 1.0 mmol) afforded 2o ( g, 0.74 mmol, 74% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.32, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.98, CHCl 3 ), 96% ee), 97.2% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 16.0 (major), 16.9 (minor); S15

16 1 H NMR (400 MHz, CDCl 3 ): δ 7.46 (d, J = 8.0 Hz, 2H), 7.24 (d, J = 8.4 Hz, 2H), 4.85 (q, J = 6.0 Hz, 1H), 1.96 (s, 1H), 1.46 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(2-bromophenyl)ethanol (2p). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(2-bromophenyl)ethanone (138 μl, 1.47 g/ml, 98%, 1.0 mmol) afforded 2p ( g, 0.82 mmol, 82% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.96, CHCl 3 ) (lit. [6] : [ ] 20 D = (c 0.6, CHCl 3 ), 77% ee), 99.2% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 12.0 (major), 13.1 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.60 (dd, J = 7.6, 2.0 Hz, 1H), 7.51 (dd, J = 8.0, 1.2 Hz, 1H), 7.35 (dt J = 7.6, 0.8 Hz, 1H), 7.13 (dt, J = 7.6, 1.6 Hz, 1H), 5.24 (q, J = 6.4 Hz,1H), 2.04 (s, 1H), 1.49 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-(trifluoromethyl)phenyl)ethanol (2q). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-(trifluoromethyl)phenyl)ethanone (209 μl, 0.92 g/ml, 98%, 1.0 mmol) afforded 2q ( g, 0.9 mmol, 90% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.20, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.01, CHCl 3 ), 96.5% ee), 93.4% ee determined by HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 95/5, 1.0 ml/min, n = 220 nm, tr 7.2 (minor), 7.8 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.61 (d, J = 8.0 Hz, 2H), 7.49 (d, J = 8.0 Hz, 2H), (m, 1H), 1.97 (d, J = 3.2 Hz, 1H), 1.50 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(3-(trifluoromethyl)phenyl)ethanol (2r). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(3-(trifluoromethyl)phenyl)ethanone (155 μl, 1.24 g/ml, 98%, 1.0 mmol) afforded 2r ( g, 0.84 mmol, 84% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.09, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.1, CHCl 3 ), 92.0% ee), 94.2% ee determined by S16

17 HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 10.9 (minor), 12.7 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.65 (s, 1H), (m, 2H), 7.46 (t, J = 7.6 Hz, 1H), (m, 1H), 1.99 (s, 1H), 1.51 (d, J = 6.8 Hz, 3H). (R)-(+)-1-(3,5-bis(trifluoromethyl)phenyl)ethanol (2s). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(3,5-bis(trifluoromethyl)phenyl)ethanone (184 μl, 1.42 g/ml, 98%, 1.0 mmol) afforded 2s ( g, 0.88 mmol, 88% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.01, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.4, CHCl 3 ), 93.6% ee), 95.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 5.3 (minor), 5.8 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.85 (s, 2H), 7.79 (s, 1H), (m, 1H), 1.96 (d, J = 4.0 Hz, 1H), 1.55 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-(methylthio)phenyl)ethanol (2t). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-(methylthio)phenyl)ethanone ( g, 98%, 1.0 mmol) afforded 2t ( g, 0.91 mmol, 91% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.05, CHCl 3 ) (lit. [7] : [ ] 20 D = (c 0.6, CHCl 3 ), 97.3% ee), 98.0% ee determined by HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 90/10, 1.0 ml/min, n = 220 nm, tr 14.0 (minor), 14.7 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.30 (d, J = 8.4 Hz, 2H), 7.25 (d, J = 8.8 Hz, 2H), (m, 1H), 2.48 (s, 3H), 1.75 (d, J = 3.6 Hz, 1H), 1.48 (d, J = 6.8 Hz, 3H). (R)-(+)-ethyl 4-(1-hydroxyethyl)benzoate (2u). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), ethyl 4-acetylbenzoate ( g, 98%, 1.0 mmol) afforded 2u ( g, 0.98 mmol, 98% yield) as a colorless oil (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.09, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.2, CHCl 3 ), 96.1% ee), 96.0% ee determined by HPLC, HPLC S17

18 conditions: Chiralcel AS-H, n-hexane/i-proh = 70/30, 1.0 ml/min, n = 220 nm, tr 13.1 (major), 20.0 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 8.01(d, J = 8.0 Hz, 2H), 7.44 (d, J = 8.0 Hz, 2H), 4.96 (q, J = 6.4 Hz, 1H), 3.91 (s, 3H), 2.07 (s, 1H), 1.50 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(4-((triisopropylsilyl)oxy)phenyl)ethanol (2v). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(4-((triisopropylsilyl)oxy)phenyl)ethanone ( g, 1.0 mmol) afforded 2v ( g, 0.84 mmol, 84% yield) as a colorless oil. IR (neat): 3370, 2945, 2868, 1603, 1485, 1279 cm -1 ; Optical Rotation: [ ] 20 D = (c 1.2, CHCl 3 ), 96.8% ee determined by HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 5.4 (minor), 7.6 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.18 (t, J = 8.0 Hz, 1H), (m, 2H), (m, 1H), 4.84 (qd, J = 6.4, 3.6 Hz, 1H), 1.78 (s, 1H), 1.47 (d, J = 6.4 Hz, 3H), (m, 3H), 1.10 (d, J = 7.2 Hz, 18H); 13 C NMR (101 MHz, CDCl 3 ) δ 156.2, 147.5, 129.3, 118.8, 117.9, 116.8, 70.2, 25.1, 17.9, 12.6; HRMS (EI) calculated for [C 17 H 30 O 2 Si] + requires m/z , found m/z (R)-(+)-1-phenylpropan-1-ol (2w). Prepared according to the general procedure, the reaction using La ( g, 0.04 mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), propiophenone (136 μl, 1.01 g/ml, 98%, 1.0 mmol) afforded 2w ( g, 0.71mmol, 71% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 1.07, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.99, CHCl 3 ), 97.5% ee), 96.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 9.8 (major), 11.0 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), (m, 1H), 4.59 (t, J = 6.4 Hz, 1H), 1.92 (s, 1H), (m, 2H), 0.91 (t, J = 7.6 Hz, 3H). (R)-(+)-1-phenylbutan-1-ol (2x). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 S18

19 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-phenylbutan-1-one (148 μl, 1.02 g/ml, 98%, 1.0 mmol) afforded 2x ( g, 0.75 mmol, 75% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.94, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 0.9, CHCl 3 ), 96.7% ee), 96.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 8.6 (major), 9.6 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), (m, 1H), (m, 1H), (m, 2H), (m, 1H), (m, 1H), (m, 1H), 0.93 (t, J = 7.2 Hz, 3H). (R)-(+)-3-chloro-1-phenylpropan-1-ol (2y). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 3-chloro-1-phenylpropan-1-one ( g, 98%, 0.98 mmol) afforded 2y ( g, 0.76mmol, 76% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.97, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.0, CHCl 3 ), 96.9% ee), 98.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 15.8 (major), 17.3 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), (m, 2H). (R)-(-)-4-chloro-1-(4-fluorophenyl)butan-1-ol (2z). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 4-chloro-1-(4-fluorophenyl)butan- 1-one (173 μl, 1.22 g/ml, 95%, 1.0 mmol) afforded 2z ( g, 0.75 mmol, 75% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.98, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.0, CHCl 3 ), 98.1% ee), 97.0% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 20.3 (minor), 22.2 (major); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2H), (m, 2H), (m, 1H), (m, 2H), 2.01 (s, 1H), (m, 4H). S19

20 (R)-(-)-2,3-dihydro-1H-inden-1-ol (2aa). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 2,3-dihydro-1H-inden-1-one ( g, 98%, 1.0 mmol) afforded 2aa ( g, 0.97 mmol, 97% yield) as a white solid. Optical Rotation: [ ] 20 D = (c 1.10, CHCl 3 ) (lit. [8] : [ ] 20 D = (c 1.00, CHCl 3 ), 67% ee), 98.0% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 14.1 (minor), 17.4 (major); 1 H NMR (400 MHz, CDCl 3 ): δ 7.41 (d, J = 5.6 Hz, 1H), (m, 3H), 5.23 (t, J = 5.6 Hz, 1H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), 1.84 (d, J = 6.0 Hz, 1H). (R)-(-)-1,2,3,4-tetrahydronaphthalen-1-ol (2ab). Prepared according to the general procedure, the reaction using La ( g, 0.04 mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 3,4-dihydronaphthalen-1(2H)-one (137 μl, 1.09 g/ml, 98%, 1.0 mmol) afforded 2x ( g, 0.73mmol, 73% yield) as a colorless oil. Optical Rotation: [ ] 20 D = (c 0.88, CHCl 3 ) (lit. [8] : [ ] 19 D = (c 1.01, CHCl 3 ), 82% ee), 94.4% ee determined by HPLC, HPLC conditions: Chiralcel AD-H, n-hexane/i-proh = 90/10, 1.0 ml/min, n = 220 nm, tr 6.1 (minor), 6.5 (major); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), (m, 2H), (m, 1H), 4.77 (s, 1H), (m, 1H), (m, 1H), (m, 5H). (R)-(+)-6,7,8,9-tetrahydro-5H-benzo[7]annulen-5-ol (2ac). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 6,7,8,9-tetrahydro-5H-benzo[7]annulen-5-one (154 μl, 1.07 g/ml, 97%, 1.0 mmol) afforded 2y ( g, 0.91 mmol, 91% yield) as a white solid. Optical Rotation: [ ] 20 D = (c 0.99, CHCl 3 ) (lit. [8] : [ ] 19 D = (c 1.88, CHCl 3 ), 88% ee), 99.6% ee determined by HPLC, HPLC conditions: Chiralcel AD-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 15.8 (major), 17.2 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.43 (d, J = 7.2 Hz, 1H), 7.20 (td, J = 7.2, 1.2 Hz, 1H), 7.15 (td, J = 7.2, 1.6 Hz, 1H), 7.10 (d, J = 7.2 Hz, 1H), 4.94 (d, J = 4.8 Hz, 1H), S20

21 2.92 (dd, J = 14.0, 8.0 Hz, 1H), (m, 1H), (m, 1H), (m, 1H), (m, 4H), (m, 1H).. (R)-(+)-1-(naphthalen-2-yl)ethanol (2ad). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (50 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (5 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(naphthalen-2-yl)ethanone ( g, 98%, 1.0 mmol) afforded 2ad ( g, 0.97 mmol, 97% yield) as a white solid (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.03, CHCl 3 ) (lit. [4] : [ ] 20 D = (c 1.02, CHCl 3 ), >99% ee), 97.6% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 21.2 (major), 24.9 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), (m, 3H), (m, 1H), 1.99 (d, J = 2.4 Hz, 1H), 1.57 (d, J = 6.8 Hz, 3H). (R)-(+)-1-(6-methoxynaphthalen-2-yl)ethanol (2ae). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(6-methoxynaphthalen-2-yl)ethanone ( g, 98%, 1.0 mmol) afforded 2ae ( g, 0.86 mmol, 86% yield) as a white solid (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.07, CHCl 3 ) (lit. [9] : [ ] 25 D =+34.3 (c 1.0, CHCl 3 ), 91% ee), 97.2% ee determined by HPLC, HPLC conditions: Chiralcel OJ-H, n-hexane/i-proh = 75/25, 1.0 ml/min, n = 220 nm, tr 15.8 (minor), 22.8 (major); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 3H), 7.47 (d, J = 8.8 Hz, 1H), (m, 2H), (m, 1H), 3.92 (s, 3H), 1.88 (d, J = 3.2 Hz, 1H), 1.57 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(benzo[b]thiophen-2-yl)ethanol (2af). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(benzo[b]thiophen-2-yl)ethanone ( g, 98%, 1.0 mmol) afforded 2af ( g, S21

22 0.84 mmol, 84% yield) as a white solid (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 0.98, CHCl 3 ) (lit. [5] : [ ] 25 D =+22.9 (c 2.89, CHCl 3 ), 93% ee), 89.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 95/5, 1.0 ml/min, n = 220 nm, tr 11.3 (major), 13.1 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), 7.71 (dd, J = 6.8, 1.6 Hz, 1H), (m, 2H), 7.18 (s, 1H), 5.19 (q, J = 6.0 Hz, 1H), 2.17 (s, 1H), 1.65 (d, J = 6.4 Hz, 3H). (R)-(+)-1-(benzofuran-2-yl)ethanol (2ag). Prepared according to the general procedure, the reaction using La ( g, mmol), CoCl 2 (100 μl, 0.1 M in THF), DCM (1 ml), NaBHEt 3 (10 μl, 0.01 mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(benzofuran-2-yl)ethanone ( g, 98%, 1.0 mmol) afforded 2ag ( g, 0.85 mmol, 85% yield) as a white solid (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 0.96, CHCl 3 ) (lit. [10] : [ ] 25 D =+16.8 (c 0.53, CHCl 3 ), 84% ee), 92.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 19.4 (major), 20.4 (minor); 1 H NMR (400 MHz, CDCl 3 ): δ 7.53 (d, J = 8.4 Hz, 1H), 7.45 (d, J = 8.0 Hz, 1H), (m, 2H), 6.60 (s, 1H), (m, 1H), 2.25 (s, 1H), 1.63 (d, J = 6.8 Hz, 3H). 1-(Pyridin-2-yl)ethanol (2ah). Prepared according to the general procedure, the reaction using La ( g, 0.04 mmol), CoCl 2 ( g, mmol), DCM (1 ml), NaBHEt 3 (25 μl, mmol), (EtO) 3 SiH (369 μl, 2.0 mmol), 1-(pyridin-2-yl)ethanone (113 μl, 1.08 g/ml, 98%, 1.0 mmol) afforded 2ah (80% HNMR yield using TMSPh as an internal standard) as a colorless oil. 0% ee determined by HPLC, HPLC conditions: Chiralcel OD-H, n-hexane/i-proh = 95/5, 0.5 ml/min, n = 220 nm, tr 17.4, 18.7; 1 H NMR (400 MHz, CDCl 3 ): δ 8.53 (d, J = 4.8 Hz, 1H), 7.70 (td, J = 8.0, 1.6 Hz,1H), 7.31 (d, J = 8.0 Hz, 1H), (m,1h), (m, 1H), 4.37 (s, 1H), 1.51 (d, J = 6.4 Hz, 3H). Gram-scale Reaction: (R)-(+)-1-(naphthalen-2-yl)ethanol (2ad). Prepared according to the general S22

23 procedure, the reaction using La ( g, mmol), CoCl 2 ( g, 0.1 mmol), DCM (1 ml), NaBHEt 3 (100 μl, 0.1 mmol), (EtO) 3 SiH (3.70 ml, 20 mmol), 1-(naphthalen-2-yl)ethanone (1.7012, 98%, 9.8 mmol) afforded 2ad ( g, 9.06mmol, 92% yield) as a white solid (purified by flash column using PE/EA = 20:1 and PE/EA = 5:1 as the eluent). Optical Rotation: [ ] 20 D = (c 1.0, CHCl 3 ) (lit [4] : [ ] 20 D = (c 1.02, CHCl 3 ), >99% ee), 98.8% ee determined by HPLC, HPLC conditions: Chiralcel AS-H, n-hexane/i-proh = 98/2, 1.0 ml/min, n = 220 nm, tr 21.0 (major), 25.5 (minor). IV. References [1] a) E. Wolinska, Tetrahedron 2013, 69, ; b) T. Xi, Y. C. Mei, Z. Lu, Org. Lett. 2015, 17, [2] H. A. McManus, P. J. Guiry, J. Org. Chem. 2002, 67, [3] M. P. Sibi, J. B. Sausker, J. Am. Chem. Soc. 2002, 124, [4] J. Guo, J. H. Chen, Z. Lu, Chem. Commun. 2015, 51, [5] X. Y. Ren, G. Li, S. M. Wei, H. F. Du, Org. Lett. 2015, 17, [6] T. C. Johnson, W. G. Totty, M. Wills, Org. Lett. 2012, 14, [7] J. X. Xu, T. Z. Wei, J. K. Xia, Q. Zhang, H. S. Wu, Chirality 2004, 16, [8] T. Kunisu, T. Oguma, T. Katsuki, J. Am. Chem. Soc. 2011, 133, [9] T. Inagaki, L. T. Phong, A. Furuta, J. Ito, H. Nishiyama, Chem. Eur. J. 2010, 16, [10] Y. S. Sokeirik, H. Mori, M. Omote, K. Sato, A. Tarui, I. Kumadaki, A. Ando, Org. Lett. 2007, 9, S23