Guanidine Catalyzed Enantioselective Desymmetrization of meso-aziridines. Electronic Supplementary Information

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1 Guanidine Catalyzed Enantioselective Desymmetrization of meso-aziridines Yan Zhang, Choon Wee Kee, Xiao Fu, Julian Ying-Teck Soh, Esther Mun Fong Loh and Choon-Hong Tan* Department of Chemistry, 3 Science Drive 3, National University of Singapore, Singapore chmtanch@nus.edu.sg Richmond Lee, Kuo-Wei Huang KAUST catalysis center and Division of Chemical and Life Sciences and Engineering, Thuwal , King Abdullah University of Science and Technology, Kingdom of Saudi Arabia Electronic Supplementary Information 1. General procedures, methods and instrumentation 1 2. Preparation and characterization of the catalysts 2 3. Desymmetrization of N-3,5-dinitrobenzoyl aziridines with thiols 4 4. Preparation and desymmetrization of cis-aziridine-2,3-dicaboxylates Desymmetrization of N-3,5-dinitrobenzoyl aziridines with carbamodithioic acids Preparation of chiral allylic amide from chiral compound 4f Preparation of chiral β-amino sulfonic acid from chiral compound 7a Determination of the absolute configuration of chiral compound 4f by X-ray crystallographic analysis Determination of the absolute configuration of chiral compound 6a by X-ray crystallographic analysis Copy of NMR spectrum Computational Study 54

2 General procedures and methods All reactions were performed in oven-dried round bottom flasks or glass vials. The flasks were fitted with rubber septa and reactions were conducted under a positive pressure of nitrogen, unless otherwise noted. All solvent distillation was done at 760 Torr. Toluene, THF, diethyl ether and diisopropyl ether were distilled from sodium wire; CH 2 Cl 2 was distilled from calcium hydride. Commercial reagents were purchased from Sigma Aldrich, Fluka, Alfa Aesar or Lancaster, and used as supplied without further purification. Analytical thin layer chromatography (TLC) was performed with Merck pre-coated TLC plates, silica gel 60F-254, layer thickness 0.25mm. Flash column chromatography was performed using Merck 60 ( mm) mesh silica gel. Instrumentation Proton nuclear magnetic resonance ( 1 H NMR) and carbon nuclear magnetic resonance ( 13 C NMR) spectra were recorded on a Bruker AMX500 (500MHz) NMR spectrometer. The residual solvent peak was used as an internal reference. Low resolution mass spectra were obtained on a Finnigan/MAT LCQ spectrometer in ESI mode. High resolution mass spectra were obtained on a Finnigan/MAT 95XL-T spectrometer. Infrared spectra were recorded on a BIO-RAD FTS 165 FTIR spectrometer. Enantiomeric excesses were determined by chiral HPLC analysis on Jasco HPLC units, including a Jasco DG Degasser, a LG Ternary Gradient Unit, a PU-980 Intelligient HPLC Pump, UV- 975 Intelligient UV/VIS Detectors, and an AS-950 Intelligient Sampler. Optical rotations were recorded on a Jasco DIP-1000 polarimeter. Melting points were determined on a BÜCHI B-540 melting point apparatus. Single crystal X-Ray diffraction studies were obtained on a Bruker-AXS Smart Apex CCD single-crystal diffractometer. 2

3 Preparation and characterization of the catalysts General procedure for the synthesis of catalysts: To a 10 ml flask containing O-protected 1-amino-2-indanol (1.1 mmol, 1.0 eq.) and 1-(Chloro-1-pyrrolidinylmethylene)pyrrolidinium hexafluorophosphate (366 mg, 1.1 mmol, 1.0 eq.) was added 5 ml of DCM, then Et 3 N (0.77 ml, 5.5 mmol, 5.0 eq.). The reaction was stirred at room temperature for 36 hours and monitored by TLC (MeOH/DCM mixture 1/4). Most of the solvent was evaporated, and the residue was directly loaded onto a silica gel column, followed by flash column chromatography (MeOH/DCM mixture, 1/50 to 1/10). 1. HPF 6 was obtained as white solid, and then it was dissolved in 5mL 2M NaOH, extracted three times with DCM, wash with brine, dried over Na 2 SO 4, and concentrated to afford catalyst 1 as pale yellow oil. (1a) (1R,2R)-2-(tert-butyldimethylsilyloxy)-N-(dipyrrolidin-1- ylmethylene)-2,3-dihydro-1h-inden-1-amine Pale yellow oil, 75% yield. [α] 27 D (c 0.89, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 0.10 (d, 6H, J = Hz), 0.90 (s, 9H), 1.86 (br, 8H), 2.79 (dd, 1H, J = 8.83, Hz), 3.11 (dd, 1H, J = 6.95, 15.1 Hz ), (br, 8H), 4.42 (m, 1H), 4.74 (d, 1H, J = 7.55 Hz,), (m, 4H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 18.9, 26.1, 26.6, 30.4, 40.0, 49.6, 70.3, 83.4, 124.5, 125.0, 127.3, 127.6, 139.9, FTIR (film): 756, 1041, 1217, 1525, 3021 cm -1. LRMS (ESI) m/z (M+H + ), HRMS (ESI) m/z (M+H + ), calc. for C 24 H 40 N 3 OSi (1b) (1R,2R)-2-(tert-butyldiphenylsilyloxy)-N-(dipyrrolidin-1- ylmethylene)-2,3-dihydro-1h-inden-1-amine Pale yellow oil, 80% yield. [α] 26 D (c 2.69, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.09 (d, 9H, J = 2.55 Hz), 1.87 (br, 8H), (m, 2H), (br, 8H), 4.58 (m, 1H), 4.98 (d, 1H, J 3

4 = 6.95 Hz), 6.98 (d, 1H, J = 6.95 Hz), (m, 3H), (m, 6H), (m, 4H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 19.9, 26.1, 27.7, 39.8, 49.3, 70.4, 84.2, 124.5, 125.0, 127.2, 127.6, 128.0, 128.2, 130.0, 130.2, 134.9, 135.3, 136.5, 136.6, 139.9, FTIR (film): 757, 1109, 1216, 1423, 1582, 3020 cm -1. LRMS (ESI) m/z (M+H + ), HRMS (ESI) m/z (M+H + ), calc. for calc. for C 34 H 44 N 3 OSi (1c) (1R,2R)-2-(benzyloxy)-N-(dipyrrolidin-1-ylmethylene)-2,3- dihydro-1h-inden-1-amine Yellow oil, 75% yield. [α] 27 D (c 1.25, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 8H), 2.90 (dd, J = 8.8, Hz, 1H), 3.22 (dd, J = 6.95, Hz, 1H), (m, 8H), 4.29 (dd, 1H, J = 7.55, Hz), 4.70 (dd, 2H, J = 11.95, Hz), 5.01 (d, 1H, J = 6.9 Hz,), (m, 4H), (m, 1H), (m, 4H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 26.1, 37.3, 49.2, 69.2, 72.7, 90.2, 124.6, 125.1, 127.3, 127.6, 128.0, 128.3, 128.9, 139.8, 139.9, 145.2, FTIR (film): 758, 929, 1047, 1216, 1422, 1525, 3020 cm -1. LRMS (ESI) m/z (M+H + ), HRMS (ESI) m/z (M+H + ), calc. for C 25 H 32 N 3 O (1d) (1R,2S)-2-(tert-butyldiphenylsilyloxy)-N-(dipyrrolidin-1- ylmethylene)-2,3-dihydro-1h-inden-1-amine Yellow oil, 70% yield. [α] 27 D +7.9 (c 1.31, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.04 (s, 9H), 1.83 (br, 8H), 2.66 (d, 1H, J = 11.3 Hz), 3.12 (dd, 1H, J = 6.35, Hz), (br, 8H), 4.48 (br, 1H), 4.81 (d, 1H, J = 5.05 Hz), 7.07 (t, 1H, J = 4.1 Hz), 7.12 (s, 2H), (m, 1H), 7.34 (t, 4H, J = 7.25 Hz), (m, 2H), (m, 4H). FTIR (film): 760, 928, 1045, 1215, 1427, 1521, 3019 cm -1. LRMS (ESI) m/z (M+H + ), HRMS (ESI) m/z (M+H + ), calc. for C 34 H 44 N 3 OSi

5 Desymmetrization of N-3,5-dinitrobenzoyl aziridines with thiols General procedure for the desymmetrization of meso N-3,5-dinitrobenzoyl aziridines with thiols: To a 10 ml flask containing catalyst 1b (0.27 mg, mmol, 1 mol %) and a stirring bar, aziridine 2c (14.6 mg, 0.05 mmol, 1.0 eq.) was added, followed by 5 ml of ether. The reaction mixture was placed in a cryobath preset at -50 o C and allowed to stir for 0.5h before 2,6-dichlorobenzenethiol (17.9 mg, 0.1 mmol, 2.0 eq.) was added. The reaction was stirred at -50 o C and monitored by TLC for 48 hours. The solvent was removed under reduced pressure and the residue was purified by flash column chromatography (silica gel, gradient elution with hexane/ea mixture, 8/1 to 4/1 and then DCM) to afford the product 4f (21.6 mg) as a white solid in 92% yield and 94% ee. 5

6 (4f) N-((1R,2R)-2-(2,6-dichlorophenylthio)cyclohexyl)-3,5- dinitrobenzamide White solid, 92% yield, 94% ee. Mp = o C. [α] 26 D (c 1.0, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 1H), (m, 2H), (m, 3H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), 6.65 (d, 1H, J = 6.95 Hz), 7.20 (t, 1H, J = 8.2 Hz), 7.38 (d, 2H, J = 7.55 Hz), 8.90 (d, 2H, J = 1.9 Hz), 9.17 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 24.5, 25.8, 32.4, 33.4, 52.9, 55.3, 120.9, 127.1, 128.9, 130.2, 132.2, 138.1, 141.5, 148.5, FTIR (film): 929, 1045, 1215, 1424, 1520, 1633, 3020, 3428 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 19 H 16 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; Phenomenex Lux 5u Cellulose- 2 (4.6 mm i.d. x 250 mm); hexane/2-propanol 80/20; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 18.6 min (major) and 22.4 min (minor). 6

7 (4g) N-((1R,2R)-2-(2,6-dichlorophenylthio)cyclopentyl)-3,5- dinitrobenzamide White solid, 94% yield, 94% ee. Mp = o C. [α] 27 D (c 1.0, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 1H), (m, 3H), (m, 1H), (m, 1H), 3.65 (q, 1H, J = 7.7 Hz), (m, 1H), 6.35 (d, 1H, J = 5.7 Hz), 7.15 (t, 1H, J = 8.2 Hz), 7.36 (d, 2H, J = 8.2 Hz), 8.75 (d, 2H, J = 1.9 Hz), 9.12 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 22.6, 31.8, 32.3, 53.0, 59.9, 121.7, 127.7, 129.5, 131.0, 132.9, 138.5, 142.3, 149.2, FTIR (film): 928, 1046, 1216, 1425, 1520, 1633, 3020, 3459 cm-1. LRMS (ESI) m/z (M- H + ), HRMS (ESI) m/z (M-H + ), calc. for C 18 H 14 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; CHIRALCEL OD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 80/20; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 29.5 min (major) and 37.1 min (minor). 7

8 (4h) N-((1R,6R)-6-(2,6-dichlorophenylthio)cyclohex-3-enyl)- 3,5-dinitrobenzamide White solid, 93% yield, 90% ee. Mp = o C. [α] 28 D (c 0.53, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 1H), (m, 2H), (m, 1H), (m, 1H), (m, 1H), (m, 1H), 5.69 (t, 2H, J = 11.5 Hz), 6.69 (d, 1H, J = 7.0 Hz), 7.19 (t, 1H, J = 8.2 Hz), 7.37 (d, 2H, J = 7.6 Hz), 8.88 (d, 2H, J = 1.9 Hz), 9.15 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 32.03, 34.5, 48.5, 51.7, 121.7, 125.0, 126.0, 127.8, 129.6, 131.0, 132.6, 138.6, 142.1, 149.3, FTIR (film): 929, 1046, 1216, 1426, 1519, 1602, 2976, 3020, 3443 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 19 H 14 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 10.9 min (major) and 12.9 min (minor). 8

9 (4i) N-((1R,2R)-2-(2,6-dichlorophenylthio)cycloheptyl)-3,5- dinitrobenzamide White solid, 91% yield, 95% ee. Mp = o C. [α] 29 D (c 0.57, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 11H), (m, 1H), (m, 1H), (m, 1H), 6.65 (d, 1H, J = 6.4 Hz), 7.19 (t, 1H, J = 7.6 Hz), 7.38 (d, 2H, J = 7.6 Hz), 8.89 (d, 2H, J = 1.9 Hz), 9.15 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 24.6, 25.0, 28.2, 32.2, 33.0, 55.4, 57.8, 120.9, 127.1, 128.9, 130.4, 132.3, 138,2, 141.7, 148.6, FTIR (film): 928, 1045, 1216, 1425, 1520, 1631, 2978, 3020, 3435 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 20 H 18 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 16.9 min (minor) and 18.9 min (major). 9

10 (4j) N-((2R,3R)-3-(2,6-dichlorophenylthio)-1,2,3,4- tetrahydronaphthalen-2-yl)-3,5-dinitrobenzamide White solid, 90% yield, 90% ee. Mp = o C. [α] 29 D (c 0.47, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 2.95 (dd, 1H, J = 8.2, 16.4 Hz), 3.19 (dd, 1H, J = 8.83, 17.0 Hz), 3.29 (dd, 1H, J = 5.68, 17.0 Hz), 3.65 (dd, 1H, J = 5.05, 17.0 Hz), (m, 1H), (m, 1H), 6.79 (d, 1H, J = 6.9 Hz), (m, 4H), 7.23 (t, 1H, J = 7.7 Hz), 7.37 (d, 2H, J = 8.2 Hz), 8.88 (s, 2H), 9.15 (s, 1H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 35.0, 35.4, 48.5, 51.8, 121.1, 126.7, 127.2, 128.6, 129.0, 129.0, 130.6, 131.7, 132.8, 133.5, 137.8, 141.5, 148.6, FTIR (film): 757, 928, 1046, 1215, 1424, 1519, 1631, 2977, 3019, 3460 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (FAB) m/z (M), calc. for C 23 H 17 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 18.1 min (major) and 23.9 min (minor). 10

11 (4k) N-((1R,2R)-2-(2,6-dichlorophenylthio)-1,2-diphenylethyl)-3,5-dinitrobenzamide White solid, 93% yield, 88% ee. Mp = o C. [α] 29 D +4.7 (c 1.60, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 5.14 (d, 1H, J = 8.2 Hz), 5.77 (t, 1H, J = 8.2 Hz), (m, 15H), 7.84 (d, 1H, J = 8.2 Hz), 9.09 (d, 2H, J = 1.9 Hz), 9.17 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 58.7, 59.4, 121.9, 127.3, 128.1, 128.5, 128.7, 128.9, 129.0, 129.1, 129.4, 131.0, 131.7, 138.1, 138.2, 139.3, 141.7, 149.4, FTIR (film): 746, 919, 1046, 1215, 1425, 1527, 1642, 2977, 3020, 3431 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (FAB) m/z (M-H + ), calc. for C 27 H 18 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 20.5 min (major) and 24.7 min (minor). 11

12 (4l) N-((2R,3R)-3-(2,6-dichlorophenylthio)butan-2-yl)-3,5- dinitrobenzamide White solid, 91% yield, 93% ee. Mp = o C. [α] 29 D (c 0.40, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 6H), (m, 1H), (m, 1H), 7.06 (d, 1H, J = 8.2 Hz), 7.29 (d, 1H, J = 9.5 Hz), 7.47 (d, 2H, J = 8.2 Hz), 9.04 (d, 2H, J = 1.9 Hz), 9.21 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 18.5, 19.1, 48.9, 51.1, 121.1, 127.1, 128.9, 130.5, 131.6, 138.0, 141.4, 148.7, FTIR (film): 928, 1045, 1216, 1425, 1520, 1643, 2977, 3020, 3446 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 17 H 14 Cl 2 N 3 O 5 S The enantiomeric excess was determined by chiral HPLC; Phenomenex Lux 5u Cellulose- 1 (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 64.8 min (minor) and 70.5 min (major). 12

13 Preparation and desymmetrization of cis-aziridine-2,3-dicaboxylate 5 Procedure for the synthesis of cis-di-tert-butyl 1-tosylaziridine-2,3-dicarboxylate 5: cis-di-tert-butyl 1-benzhydrylaziridine-2,3-dicarboxylate (12) was prepared by literature procedure. 1 White solid, 60% yield. Mp = o C. 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.46 (s, 18H), 2.52 (s, 2H), 3.83 (s, 1H), (m, 2H), (m, 4H), 7.57 (d, 4H, J = 6.95 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 28.0, 44.4, 76.7, 81.6, 127.3, 127.4, 128.4, 142.0, FTIR (film): 929, 1046, 1216, 1477, 1633, 2977, 3020, 3452 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. For C 25 H 31 NO 4 Na cis-di-tert-butyl 1-tosylaziridine-2,3-dicarboxylate (5) To a solution of 12 (409 mg, 1.0 mmol) in MeOH/DCM mixture 1/1 (20 ml) was added Pd(OH) 2 /C (170mg). Bubbling of hydrogen gas for 15 minutes, the reaction was stirred for a further 4 hours under a positive atmosphere of hydrogen gas (balloon). The reaction mixture was filtered through a thin layer of celite and the solvent was evaporated under reduced pressure, affording aziridine 13 as colorless oil, which was used for next step without purification. The crude azirdine 13 was dissolved in DCM (5 ml) and cooled to 0 o C. TsCl (381 mg, 2 mmol, 2.0 eq.) was added in one portion, followed by pyridine (237 mg, 3 mmol, 3.0 eq.). The reaction mixture was stirred at 0 o C for 1 hour. Most of the solvent was evaporated, and the residue was directly loaded onto a silica gel column, followed by flash column chromatography (hexane/ea mixture, 8/1 to 4/1) to afford 5 (277.9 mg, 0.7 mmol) as a white solid in 70% yield (2 steps). Mp = o C. 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.40 (s, 18H), 2.42 (s, 3H), 3.43 (s, 2H), 7.33 (d, 2H, J = 8.2 Hz), 7.88 (d, 2H, J = 8.2 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 22.4, 28.5, 42.0, 84.0, 128.9, 130.4, 134.8, 145.8, FTIR (film): 771, 928, 1045, 1216, 1370, 1477, 1643, 1749, 2980, 3020, 3430 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. For C 19 H 27 NO 6 SNa [1] Williams, A. L.; Johnston, J. N. J. Am. Chem. Soc. 2004, 126,

14 General procedure for the desymmetrization of cis-aziridine 5 with thiols: To a 10 ml flask containing catalyst 1b (2.7 mg, mmol, 10 mol %) and a stirring bar, aziridine 5 (19.9 mg, 0.05 mmol, 1.0 eq.) was added, followed by 10 ml of diisopropyl ether. The reaction mixture was placed in a cryobath preset at -50 o C and allowed to stir for 0.5h before thiol (0.25 mmol, 5.0 eq.) was added. The reaction was stirred at -50 o C and monitored by TLC for 48 hours. The solvent was removed under reduced pressure and the residue was purified by flash column chromatography (silica gel, gradient elution with hexane/ea mixture, 8/1 to 4/1). (6a) (2R,3R)-di-tert-butyl 2-(2,6-dichlorophenylthio)-3-(4- methylphenylsulfonamido)succinate White solid, 91% yield, 88% ee. Mp = o C. [α] 29 D (c 1.30, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.35 (s, 18H), 2.40 (s, 3H), 4.08 (d, 1H, J = 3.8 Hz), 4.26 (dd, 1H, J = 3.8, 7.6 Hz), 5.65 (d, 1H, J = 7.55 Hz), 7.20 (t, 1H, J = 8.2 Hz), 7.27 (d, 2H, J = 8.2 Hz), 7.39 (d, 2H, J = 8.2 Hz), 7.75 (d, 2H, J = 8.2 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 22.2, 28.2, 28.4, 54.0, 57.6, 83.5, 84.7, 128.1, 129.4, 130.3, 130.9, 133.4, 137.2, 141.7, 144.3, 168.1, FTIR (film): 758, 928, 1045, 1159, 1216, 1349, 1424, 1522, 1642, 1731, 2980, 3020, 3436 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M+Na + ), calc. for C 25 H 31 Cl 2 NO 6 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 95/05; flow rate 0.5 ml/min; temp 25 C; detection UV 210 nm; retention time: 33.6 min (minor) and 36.2 min (major). 14

15 (6b) (2R,3R)-di-tert-butyl 2-(2,6-dimethylphenylthio)-3-(4- methylphenylsulfonamido)succinate White solid, 97% yield, 90% ee. Mp = o C. [α] 29 D (c 1.41, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.33 (d, 18H, J = 13.9 Hz), 2.40 (s, 3H), 2.52 (s, 6H), 3.76 (d, 1H, J = 4.4 Hz), 4.27 (dd, 1H, J = 4.45, 7.6 Hz), 5.58 (d, 1H, J = 7.55 Hz), (m, 3H), 7.27(d, 2H, J = 8.2 Hz), 7.68 (d, 2H, J = 8.8 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 21.5, 22.0, 27.6, 27.7, 53.7, 57.4, 82.6, 83.7, 127.4, 128.3, 128.8, 129.6, 132.2, 136.5, 143.2, 143.6, 167.7, FTIR (film): 759, 928, 1045, 1159, 1216, 1426, 1522, 1642, 1733, 2980, 3020, 3436 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M+Na + ), calc. for C 27 H 37 NO 6 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 210 nm; retention time: 8.4 min (minor) and 9.9 min (major). 15

16 Desymmetrization of N-3,5-dinitrobenzoyl aziridines with carbamodithioic acids General procedure for the desymmetrization of meso N-3,5-dinitrobenzoyl Aziridines with carbamodithioic acids: To a 10 ml flask containing catalyst 1b (2.7 mg, mmol, 10 mol %) and a stirring bar, aziridine 2c (14.6 mg, 0.05 mmol, 1.0 eq.) was added, followed by 2.5 ml of ether, and CS 2 (7.2 μl, 0.12 mmol, 2.4 eq.). The reaction mixture was placed in a cryobath preset at -50 o C and allowed to stir for 0.5h before bis(2-methoxybenzyl)amine (15.4 mg, 0.06 mmol, 1.2 eq.) was added. The reaction was stirred at -50 o C and monitored by TLC for 24 hours. The solvent was removed under reduced pressure and the residue was purified by flash column chromatography (silica gel, gradient elution with hexane/ea mixture, 8/1 to 4/1 and then DCM) to afford the product 7a (30.7 mg) as a white solid in 98% yield and 89% ee. 16

17 (7a) (1R,2R)-2-(3,5-dinitrobenzamido)cyclohexyl bis(2- methoxybenzyl)carbamodithioate White solid, 98% yield, 89% ee. 96% ee was obtained after recrystallization from DCM/Hexane. Mp = o C. [α] 29 D (c 0.54, CHCl 3 ) (96% ee). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 3H), (m, 1H), (m, 2H), 2,21 (d, 1H, J = 13.3 Hz), 2,41 (d, 1H, J = 7.6 Hz), 3.74 (s, 6H), (m, 1H), (m, 1H), 5.00 (dd, 2H, J = 17.0, 34.1 Hz), 5.25 (d, 1H, J = 15.8 Hz), 5.44 (d, 1H, J = 15.8 Hz), 6.44 (t, 1H, J = 7.6 Hz), 6.68 (t, 1H, J = 7.6 Hz), 6.77 (d, 1H, J = 8.2 Hz), 6.82 (t, 2H, J = 9.2 Hz), 6.90 (d, 1H, J = 7.6 Hz), 7.09 (t, 1H, J = 7.6 Hz), 7.20 (t, 1H, J = 7.6 Hz), 8.71 (d, 1H, J = 6.9 Hz), 9.07 (s, 3H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 24.5, 26.6, 32.2, 33.9, 51.6, 53.9, 54.0, 55.2, 55.2, 57.6, 110.3, 110.3, 119.8, 120.4, 120.7, 122.2, 123.2, 126.5, 126.8, 127.7, 128.4, 128.9, 137.8, 148.4, 156.9, 157.2, 161.7, FTIR (film): 756, 927, 1030, 1110, 1216, 1344, 1437, 1467, 1493, 1544, 1664, 2977, 3020, 3456 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. for C 30 H 32 N 4 O 7 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 15.0 min (minor) and 18.4 min (major). after recrystallization 17

18 (7b) (1R,2R)-2-(3,5-dinitrobenzamido)cyclopentyl bis(2- methoxybenzyl)carbamodithioate White solid, 98% yield, 85% ee. 91% ee was obtained after recrystallization from DCM/Hexane. Mp = o C. [α] 29 D (c 2.14, CHCl 3 ) (85% ee). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 1H), (m, 3H), (m, 1H), (m, 1H), 3.76 (d, 6H, J = 12.6 Hz), (m, 1H), (m, 1H), 4.93 (d, 1H, J = 17.0 Hz), 5.10 (d, 2H, J = 17.8 Hz), 5.56 (d, 1H, J = 15.8 Hz), 6.46 (t, 1H, J = 7.6 Hz), 6.77 (d, 1H, J = 8.2 Hz), (m, 3H), 6.99 (d, 1H, J = 7.6 Hz), 7.05 (t, 1H, J = 7.6 Hz), 7.25 (m, 1H), 8.74 (d, 1H, J = 5.1 Hz), (m, 3H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 21.0, 27.7, 31.7, 51.9, 52.4, 54.0, 55.2, 55.2, 62.1, 110.2, 110.3, 119.9, 120.6, 120.7, 122.2, 123.1, 126.6, 126.8, 127.6, 128.3, 129.0, 137.5, 148.5, 156.9, 156.9, 162.6, FTIR (film):759, 928, 1046, 1216, 1424, 1476, 1530, 1640, 2977, 3020, 3451 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 29 H 29 N 4 O 7 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 18.5 min (minor) and 23.0 min (major). after recrystallization 18

19 (7c) (1R,6R)-6-(3,5-dinitrobenzamido)cyclohex-3-enyl bis(2-methoxybenzyl)carbamodithioate White solid, 80% yield, 84% ee. 95% ee was obtained after recrystallization from DCM/Hexane. Mp = o C. [α] 31 D -7.1 (c 0.53, CHCl 3 ) (84% ee). 1 H NMR (500 MHz, CDCl 3, ppm): δ 2,26 (t, 1H, J = 12.0 Hz), 2,51 (t, 1H, J = 13.3 Hz), 2.63 (d, 1H, J = 17.0 Hz), 2.84 (d, 1H, J = 17.0 Hz), 3.73 (s, 3H), 3.74 (s, 3H), (m, 1H), (m, 1H), 4.99 (s, 2H), 5.37 (s, 2H), 5.71 (d, 2H, J = 10.7 Hz), 6.50 (t, 1H, J = 7.6 Hz), 6.64 (t, 1H, J = 7.6 Hz), 6.80 (t, 2H, J = 8.2 Hz), 6.90 (t, 2H, J = 6.3 Hz), 7.12 (t, 1H, J = 7.6 Hz), 7.19 (t, 1H, J = 8.2 Hz), 8.85 (d, 1H, J = 7.6 Hz), 9.09 (s, 2H), 9.10 (s, 1H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 31.4, 33.5, 50.4, 51.7, 53.5, 54.0, 55.2, 55.2, 110.3, 110.3, 119.9, 120.4, 120.8, 122.1, 123.1, 125.3, 126.5, 127.1, 127.7, 128.5, 129.0, , 148.5, 150.0, 156.9, 156.9, 161.9, FTIR (film): 771, 928, 1031, 1218, 1344, 1433, 1470, 1532, 1665, 2975, 3020, 3443 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. for C 30 H 30 N 4 O 7 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 18.7 min (minor) and 34.8 min (major). after recrystallization 19

20 (7d) (1R,2R)-2-(3,5-dinitrobenzamido)cycloheptyl bis(2- methoxybenzyl)carbamodithioate White solid, 67% yield, 80% ee. 90% ee was obtained after recrystallization from DCM/Hexane. Mp = o C. [α] 30 D -8.4 (c 0.45, CHCl 3 ) (90% ee). 1 H NMR (500 MHz, CDCl 3, ppm): δ 1.66 (m, 3H), (m, 4H), (m, 1H), (m, 2H), 3.74 (s, 6H), (m, 1H), (m, 1H), 4.97 (dd, 2H, J = 17.0, 32.2 Hz), 5.29 (d, 1H, J = 15.8 Hz), 5.40 (d, 1H, J = 15.8 Hz), 6.48 (t, 1H, J = 7.6 Hz), 6.64 (t, 1H, J = 7.0 Hz), 6.80 (dd, 2H, J = 8.2, 12.7 Hz), 6.87 (t, 2H, J = 7.6 Hz), 7.10 (t, 1H, J = 8.2 Hz), 7.18 (t, 1H, J = 7.6 Hz), 8.68 (d, 1H, J = 7.0 Hz), 9.06 (s, 2H), 9.07(s, 1H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 24.7, 27.0, 27.9, 30.4, 33.6, 34.6, 52.2, 54.7, 55.9, 55.9, 57.5, 60.0, 110.9, 111.0, 120.5, 121.0, 121.4, 122.9, 123.9, 127.2, 127.7, 128.4, 129.1, 129.6, 138.5, 149.1, 157.6, 157.9, 162.2, FTIR (film): 771, 927, 1030, 1109, 1216, 1344, 1436, 1465, 1493, 1545, 1663, 2974, 3019, 3431 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. for C 31 H 34 N 4 O 7 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 15.7 min (minor) and 19.0 min (major). after recrystallization 20

21 (7e) (1R,2R)-2-(3,5-dinitrobenzamido)cycloheptyl bis(2- methoxybenzyl)carbamodithioate White solid, 91% yield, 90% ee. 98% ee was obtained after recrystallization from DCM/Hexane. Mp = o C. [α] 29 D (c 0.66, CHCl 3 ) (90% ee). 1 H NMR (500 MHz, CDCl 3, ppm): δ 3.70 (s, 3H), 3.76 (s, 3H), 4.93 (d, 1H, J = 17.0 Hz), 5.08 (d, 1H, J = 17.0 Hz), 5.26 (d, 1H, J = 15.8 Hz), 5.58 (dd, 1H, J = 7.6, 11.4 Hz), 5.65 (d, 1H, J = 15.8 Hz), 6.00 (d, 1H, J = 11.9 Hz), 6.51 (t, 1H, J = 7.6 Hz), 6.60 (t, 1H, J = 7.6 Hz), 6.80 (dd, 2H, J = 8.2, 20.2 Hz), 6.90 (d, 1H, J = 7.6 Hz), 6.99 (d, 1H, J = 7.6 Hz), (m, 10H), 7.34 (d, 1H, J = 7.0 Hz), 9.11 (s, 3H), 9.56 (d, 1H, J = 7.6 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 51.5, 54.1, 55.1, 55.3, 60.9, 61.6, 110.3, 110.4, 120.0, 120.3, 120.8, 122.1, 123.1, 126.7, 127.4, 127.7, 127.8, 128.1, 128.5, 128.6, 128.7, 128.8, 129.1, 136.9, 137.6, 139.8, 148.5, 157.0, 157.4, 161.7, FTIR (film): 771, 1092, 1218, 1452, 1642, 3435 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M+H + ), calc. for C 38 H 35 N 4 O 7 S The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 13.3 min (minor) and 37.2 min (major). after recrystallization 21

22 Preparation of chiral allylic amide from chiral compound 4f N-((1R,2R)-2-(2,6-dichlorophenylsulfinyl)cyclohexyl)-3,5-dinitrobenzamide (8) To a solution of 4f (94.0 mg, 0.20 mmol, 1.0 eq.) in CH 2 Cl 2 2 ml was added mcpba (70% W/W, 49.3 mg, 0.20 mmol, 1.0 eq.). The reaction mixture was stirred at room temperature for 15 minutes. Most of the solvent was evaporated, and the residue was directly loaded onto a silica gel column, followed by flash column chromatography (hexane/ea mixture, 8/1 to 1/1) to afford 8 (97.0 mg, 0.2 mmol) as a white solid in quantitative yield. Mp = o C. [α] 28 D (c 0.50, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 5H), (m, 2H), 2.65 (d, 1H, J = 10.1 Hz), (m, 1H), (m, 1H), 7.41 (d, 2H, J = 4.5 Hz), 7.87 (s, 1H), 9.07 (d, 2H, J = 2.5 Hz), 9.10 (d, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 24.7, 26.0, 26.8, 34.0, 55.5, 64.1, 121.6, 128.3, 134.0, 135.6, 139.1, 149.3, FTIR (film): 753, 1045, 1215, 1344, 1427, 1543, 1669, 2976, 3020, 3442 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. for C 19 H 17 Cl 2 N 3 O 6 SNa (R)-N-(cyclohex-2-enyl)-3,5-dinitrobenzamide (9) To a 5 ml flask containing 8 (38.8 mg, 0.08 mmol, 1.0 eq.) was added 1 ml of toluene, then K 2 CO 3 (331 mg, 2.4 mmol, 30.0 eq.). The reaction was stirred under N 2 and heated under reflux for 3 days. The reaction mixtue was filtered and most of the solvent was evaporated under reduced pressure. The residue was directly loaded onto a silica gel column, followed by flash column chromatography (hexane/ea mixture, 20/1 to 8/1) to afford 9 (13.9 mg, mmol) as a white solid in 60% yield and 95% ee. Mp = o C. [α] 29 D (c 0.30, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 3H), (m, 3H), 4.74 (br, 1H), 5.69 (dd, 1H, J = 2.5, 9.5 Hz), (m, 1H), 6.25 (d, 1H, J = 5.7 Hz), 8.93 (d, 2H, J = 2.5 Hz), 9.16 (t, 1H, J = 1.9 Hz). 13 C NMR (125 MHz, CDCl 3, ppm): δ 22

23 20.3, 25.5, 29.9, 46.8, 121.7, 127.0, 127.8, 133.3, 138.9, 149.3, FTIR (film): 767, 928, 1045, 1216, 1344, 1424, 1528, 1643, 2976, 3020, 3434 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M-H + ), calc. for C 13 H 12 N 3 O The enantiomeric excess was determined by chiral HPLC; CHIRALPAK AD-H (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 9.1 min (major) and 10.5 min (minor). 23

24 Preparation of chiral β-amino sulfonic acid from chiral compound 7a (1R,2R)-2-(bis(2-methoxybenzyl)carbamothioylthio)cyclohexylcarbamate (10) To a solution of 7a (62.4 mg, 0.1 mmol, 1.0 eq.) in THF (1 ml), Boc 2 O (47 μl, 0.2 mmol, 2.0 eq.), Et 3 N (42 μl, 0.3 mmol, 3.0 eq.) and DMAP (2.5mg, 0.02 mmol, 20 mol%) were added and the mixture was stirred at room temperature for 48 hours. 6M NaOH (1 ml) was added and the mixture was stirred at room temperature for 2 hours. Water was added and the mixture was extracted with ethyl acetate three times. Combined organic layer was washed with brine, dried over NaSO 4 and concentrated. The residue was purified by flash column chromatography (silica gel, hexane/ea mixture, 8/1 to 4/1) to afford 10 (41.1 mg, mmol) as a white solid in 78% yield (2 steps) and 96% ee. Mp = o C. [α] 29 D (c 0.35, CHCl 3 ). 1 H NMR (500 MHz, CDCl 3, ppm): δ (m, 3H), 1.43 (s, 9H), (m, 1H), 1.74 (m, 2H), 2.25 (m, 2H), 3.50 (m, 1H), 3.74 (s, 3H), 3.76 (s, 3H), (m, 1H), 4.99 (dd, 2H, J = 17.7, 30.3 Hz), 5.30 (d, 1H, J = 15.8 Hz), 5.42 (d, 1H, J = 15.8 Hz), 5.56 (d, 1H, J = 7.6 Hz), 6.84 (d, 2H, J = 8.2 Hz), (m, 2H), 7.03 (d, 1H, J = 7.0 Hz), 7.18 (d, 1H, J = 7.0 Hz), (m, 2H). 13 C NMR (125 MHz, CDCl 3, ppm): δ 25.5, 27.0, 27.5, 29.1, 33.9, 35.6, 51.5, 53.7, 55.3, 55.7, 56.6, 79.4, 110.7, 110.8, 121.2, 123.4, 124.1, 127.2, 128.2, 129.0, 129.1, 156.3, 157.5, 157.8, FTIR (film): 760, 928, 1046, 1217, 1424, 1473, 1518, 1603, 1696, 2977, 3020, 3443 cm -1. LRMS (ESI) m/z (M+Na + ), HRMS (ESI) m/z (M+Na + ), calc. for C 28 H 38 N 2 O 4 S 2 Na The enantiomeric excess was determined by chiral HPLC; CHIRALPAK IA (4.6 mm i.d. x 250 mm); hexane/2-propanol 90/10; flow rate 1.0 ml/min; temp 25 C; detection UV 230 nm; retention time: 6.4 min (minor) and 7.9 min (major). 24

25 (1R,2R)-2-aminocyclohexane-1-sulfonic acid (11) To a 10 ml flask containing 10 (77.0 mg, mmol) was added 98% formic acid (5.25 ml). H 2 O 2 (30% W/W, 2.25 ml) was added dropwise. The reaction mixture was stirred at room temperature for 3 days. After removal of the solvent under reduced pressure, the crude product was further purified via recrystallization from methanol and diethyl ether, to afford 11 (23.8 mg, mmol) as a white solid in 92% yield. Mp = 410 o C dec. [α] 32 D (c 1.14, H 2 O). 1 H NMR (500 MHz, D 2 O, ppm): δ (m, 2H), (m, 2H), (m, 2H), (m, 2H), 2.93 (dt, 1H, J = 3.8, 11.4 Hz), 3.38 (dt, 1H, J = 3.8, 11.4 Hz). 13 C NMR (125 MHz, D 2 O, ppm): δ 23.5, 23.6, 26.4, 30.2, 50.4, FTIR (KBr): 1039, 1184, 1385, 1447, 1509, 1531, 1595, 1617, 2854, 2926,3139, 3443 cm -1. LRMS (ESI) m/z (M-H + ), HRMS (ESI) m/z (M+H + ), calc. for C 6 H 14 NO 3 S

26 Determination of the absolute configuration of chiral compound 4f by X-ray Crystallographic analysis The crystal is monoclinic, space group P2(1). The asymmetric unit contains one molecule of the compound C19H17Cl2N3O5S. The H atom H1N was located from different map and refined with restraints in bond length and thermal parameters. Final R values are R1= and wr2= for 2-theta max of 55º. Crystal data and structure refinement for Identification code 9440 Empirical formula C19 H17 Cl2 N3 O5 S Formula weight Temperature 223(2) K Wavelength Å Crystal system Monoclinic Space group P2(1) 26

27 Unit cell dimensions a = (6) Å = 90. b = (5) Å = (2). c = (13) Å = 90. Volume (13) Å 3 Z 2 Density (calculated) Mg/m 3 Absorption coefficient mm -1 F(000) 484 Crystal size 0.26 x 0.24 x 0.04 mm 3 Theta range for data collection 1.17 to Index ranges Reflections collected <=h<=10, -8<=k<=7, -22<=l<=23 Independent reflections 3546 [R(int) = ] Completeness to theta = % Absorption correction Semi-empirical from equivalents Max. and min. transmission and Refinement method Full-matrix least-squares on F 2 Data / restraints / parameters 3546 / 2 / 274 Goodness-of-fit on F Final R indices [I>2sigma(I)] R1 = , wr2 = R indices (all data) R1 = , wr2 = Absolute structure parameter 0.01(9) Largest diff. peak and hole and e.å -3 27

28 Determination of the absolute configuration of chiral compound 6a by X-ray Crystallographic analysis The crystal is triclinic, space group P-1. The asymmetric unit contains one molecule of the compound C25H31NO6S2Cl2. Final R values are R1= and wr2= for 2-theta max of 55º. Crystal data and structure refinement for A106. Identification code a106 Empirical formula C25 H31 Cl2 N O6 S2 Formula weight Temperature 273(2) K Wavelength Å Crystal system Triclinic Space group P-1 28

29 Unit cell dimensions a = (10) Å = (2). b = (11) Å = (2). c = (17) Å = (2). Volume (3) Å 3 Z 2 Density (calculated) Mg/m 3 Absorption coefficient mm -1 F(000) 604 Crystal size 0.56 x 0.18 x 0.08 mm 3 Theta range for data collection 1.34 to Index ranges Reflections collected <=h<=12, -13<=k<=13, -21<=l<=21 Independent reflections 6589 [R(int) = ] Completeness to theta = % Absorption correction Semi-empirical from equivalents Max. and min. transmission and Refinement method Full-matrix least-squares on F 2 Data / restraints / parameters 6589 / 27 / 342 Goodness-of-fit on F Final R indices [I>2sigma(I)] R1 = , wr2 = R indices (all data) R1 = , wr2 = Largest diff. peak and hole and e.å -3 29

30 Integral Supplementary Material (ESI) for Chemical Communications Copy of NMR spectrum 1H AMX500 zhy cat TBS C AMX500 zhy cat TBS

31 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy cat trans basify C AMX500 zhy cat trans basify

32 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy cat Bn C AMX500 zhy cat Bn

33 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy cat cis basify

34 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy8236a C AMX500 zhy zhy8236a

35 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zy zhy8236b C AMX500 zhy zhy8236b

36 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zy zhy8236c C AMX500 zhy zhy8236c

37 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy8259d C AMX500 zhy zhy8237c

38 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy8237a C AMX zhy8237a

39 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy8237b C AMX500 zhy b in CDCl

40 Integral Supplementary Material (ESI) for Chemical Communications amx500 zhy zhy C AMX500 zhy zhy

41 Integral Supplementary Material (ESI) for Chemical Communications amx1h-500 my20zhy1.1 zhy C AMX500 zhy zhy

42 Integral Supplementary Material (ESI) for Chemical Communications amx1h-500 my20zhy1.1 zhy C AMX500 zhy ZHY8185S

43 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy8185a C AMX500 zhy ZHY8185B

44 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500zyj zhy ZHY8185A C AMX500 zhy ZHY8185A

45 Integral Supplementary Material (ESI) for Chemical Communications amx500 zhy zhy C AMX500 zhy zhy

46 Integral H amx500 zhy zhy9022b Supplementary Material (ESI) for Chemical Communications

47 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy9022a

48 Integral Supplementary Material (ESI) for Chemical Communications 1H AMX500 zhy zhy9030a C AMX500 zhy zhy9030a