Supporting Information

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1 Supporting Information Preparation of α-acyloxy Ketones via Visible-Light-Induced Aerobic xo-acyloxylation of lefins with Carboxylic Acids Qing-Bao Zhang, a Yong-Liang Ban, a Da-Gang Zhou, a Pan-Pan Zhou, a Li-Zhu Wu b and Qiang Liu* a a State Key Laboratory of Applied rganic Chemistry, Lanzhou University, Lanzhou , P. R. China. liuqiang@lzu.edu.cn b Key Laboratory of Photochemical Conversion and ptoelectronic Materials, Technical Institute of Physics and Chemistry, the Chinese Academy of Sciences, Beijing , P. R. China. lzwu@mail.ipc.ac.cn. 1

2 Table of Contents 1. General information Photophysical properties General experimental procedure for the reaction General procedure for the synthesis of alkenoic acids General procedure for the synthesis of products General procedure for the proparation of 2a-2o General procedure for the proparation of 5aa-5ea and 5ab-5af Mechanistic investigations The radical trapping experiment Calculation studies Characterization data Characterization data of substrates Characterization data of the products References NMR Spectra NMR Spectra of the substrates NMR Spectra of the products

3 1. General information. 1 H NMR and 13 C NMR spectra weree recorded on Bruker AM-400 MHz instruments, and the chemical shifts (δ) are reported in ppm and coupling constants (J) in Hz. Spectra were referenced to internal TMS (0.00ppm, 1 H) and residual chloroform (77.23 ppm, 13 C). Abbreviations are used in the description of NMR data as follows: chemical shift (δ, ppm), multiplicity (s = singlet, d = doublet, t = triplet, q =quartet, m = multiplet), coupling constant (J, Hz). Mass spectra were obtained on Bruker Daltonics Dataa Analysis 3.4: Esquire6000. All luminescencee spectra were surveyed on a RF-5301PC fluorescence (FL) spectrophotometer using 5/2.5 and 5/55 nm slit width, and equipped with a 1-cm quartz cell. Infrared spectra (IR) were recorded on a Nicolet (MX-1E FT-IR) spectrometer. Column chromatography was performed with silica gel ( meshes). Materials were obtained from commercial suppliers or prepared according to standard procedures unless otherwise noted. 2. Photophysical properties. Figure S1. UV-Vis absorption spectra of 1a and PC. 3

4 Figure S2. Fluorescence quenching by reaction substrate. (a) Luminescence quenching of PC (1 x 10-4 M) with progressive addition of 1a in the air. (b) Luminescence quenching of PC (1.0 x 10-4 M) with progressive addition of 1a in argon. (C) Stern-Volmer plots of fluorescence quenching by reaction substrate 1a. 3. General experimental procedure for the reaction. 3.1 General procedure for the synthesis of alkenoic acids. Method A: Target substrates were synthesized by the modified references procedure(ying-yeung Yeung et al. rg. Lett., 2011, 13, ). (3-carboxypropyl)triphenylphosphonium bromide (924 mg, 2.16 mmol, 1.08 eq) was suspended in THF (12 ml) at -20 C. NaHMDS (2.16 ml, 4.32 mmol, 2.16 eq) was added dropwise into the suspension and further stirred for 20 min. The reaction mixture was then cooled to -78 C and the corresponding aldehyde (2.0 mmol, 1.0 eq) was added. After 18 h, the solvent was removed in vacuo. H 2 (60 ml) was added to the residue and extracted with diethyl ether (3 x 20 ml). The diethyl ether layers were discarded while the H 2 layer was acidified to PH= 2 using HCl (1 M). The acidified aqueous layer was further extracted with ethyl acetate (3 x 20 ml). The organic layers were combined, dried over sodium sulfate, filtered and concentrated to dryness. The alkenoic acid was purified over silica gel using ethyl acetate:hexane (1:1). The alkenoic acid was further recrystallized using hexane and ethyl acetate. Method B: Target substrates were synthesized by the modified references procedure (Thomas Wirth et al rg. Lett., 2011, 13, ). A mixture of iodobenzene (1.0 mmol), 4-pentenoic acid (0.8 mmol), triethylamine 4

5 (2.0 mmol, ml), palladium acetate (21 mg, 0.02 mmol) and triphenylphosphine (0.96 mmol, 251 mg) were heated under reflux at 80 C for 3 h. Solid products were isolated by diluting the reaction mixtures with 10% hydrochloric acid (200 ml) with stirring to dissolve the salts and excess amine. Finally, the residue was purified by column chromatography by using 1% methanol in chloroform. 3.2 General procedure for the synthesis of products General procedure for the proparation of 2a-2o. To a 10 ml pyrex glass tube which equipped with a magnetic stirring bar were added alkenoic acid (0.1 mmol), 9-mesityl-10-methylacridinium perchlorate (5 mol%) and DABC (1.0 equiv), followed by thymoquinone (0.2 equiv, just for Table 4), MS 4Å (40 mg) and fresh distilled acetonitrile (3.0 ml). The vial was then irradiated with 450 nm blue LEDs at room temperature.the reaction was monitored by TLC until alkenoic acid was no longer consumed. Then the solvent was removed under reduced pressure and the residue was purified by column chromatography using petroleum ether/ethyl acetate to afford the desired product General procedure for the proparation of 5aa-5ea and 5ab-5af. To a 10 ml pyrex glass tube which equipped with a magnetic stirring bar were added acid (10.0 equiv), 9-mesityl-10-methylacridinium perchlorate (5 mol%) and DABC (3.0 equiv), followed by thymoquinone (0.5 equiv, just for Table 4), MS 4Å (40 mg), fresh distilled acetonitrile (3.0 ml)and aromatic olefin (0.2 mmol, 1 equiv). The vial was then irradiated with 450 nm blue LEDs at room temperature.the reaction was monitored by TLC until aromatic olefin was no longer consumed. Then the solvent was removed under reduced pressure and the residue was purified by column chromatography using petroleum ether/ethyl acetate to afford the desired product. 4.Mechanistic investigations 5

6 4.1 The radical trapping experiment. Me H 450nm LEDs, air Mes-Acr + (5 mol %) DABC (1 equiv), MS 4Å TEMP(2 equiv) ), CH 3 CN N + Me Me To a 10 ml Schlenk tube which equipped with a magnetic stirring bar were added 1a (0.1 mmol), 9-mesityl-10-methylacridinium perchlorate (5 mol%) and DABC (1.0 equiv), followed by TEMP (2.0 equiv), MS 4Å (40 mg) and fresh distilled acetonitrile (3. 0 ml). The mixture was irradiated with 450 nm blue LEDs at room temperature for 10 hours. the reaction was monitored by TLC and was characterized by high resolution mass spectra, 1 H NMR and 13 C NMR. 6

7 7

8 4.2 Calculation studies Scheme1. Free energy profile for the proposed intermediates and transition states. All the calculations were performed with the Gaussian09 suite of programs. 12 The intermediates and transition states are calculated at the B3LYP/6-31+G(d,p) level of theory in the gas phase. According to the literatures, there may be two paths (a and b) to obtain the product 2m. In the path a, the process E1 D1 may be the rate-determining step, with the energy barrier of kcal/mol in the TSa. However, the experimental results showed that the path b is also another path to get the final product 2m. In path b, the alkene radical cation A firstly loses one proton to become A1, and a ring-closing reaction of A1 produces B via the transition state TSb. The energy to overcome the energy barrier is 6.15 kcal/mol. Therefore, path b is more plausible to produce the product 2m. 8

9 5. Characterization data. 5.1 Characterization data of substrates. (E)-5-(4-methoxyphenyl)pent-4-enoic acid (1a) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.28 (s, 2H), 6.85 (d, J=8.5 Hz, 2H), 6.41 (d, J=15.8 Hz, 1H), (m, 1H), 3.80 (s, 3H), 2.53 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.9, 176.6, 164.6, 131.4, 126.8, 114.4, 78.3, 55.8, 27.1, 25.2 ppm. MS (ESI, m/z): Calculated for [C 12 H 14 3 ] (M+H) found Characterization data obtained for 1a matched those previously reported in the literature. 1 (E)-5-(4-methoxyphenyl)-2-methylpent-4-enoic acid (1b) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.29 (d, J=8.7 Hz, 2H), 6.85 (d, J=8.7 Hz, 2H), 6.41 (d, J=14.6 Hz, 1H), (m, 1H), 3.80 (s, 3H), (m, 2H), (m, 1H), 1.24 (d, J=6.8 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 182.5, 159.2, 132.0, 130.4, 127.5, 124.8, 114.2, 55.5, 39.8, 36.9, 16.6 ppm. MS (ESI, m/z): Calculated for [C 13 H 16 3 ] (M+H) found (E)-5-(4-methoxyphenyl)-3-methylpent-4-enoic acid (1c) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.29 (d, J=8.6 Hz, 2H), 6.85 (d, J=8.7 Hz, 2H), 6.39 (d, J=15.9 Hz, 1H), (m, 1H), 3.80 (s, 3H), (m, 1H), (m, 2H), 1.18 (d, J=6.8 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 178.8, 159.1, 131.9, 130.3, 128.6, 127.5, 114.2, 55.5, 41.7, 33.8, 20.5 ppm. MS (ESI, m/z): Calculated for [C 13 H 16 3 ] (M+H) found

10 (E)-5-(4-methoxyphenyl)-3,3-dimethylpent-4-enoic acid (1d) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.29 (d, J=8.6 Hz, 2H), 6.84 (d, J=8.6 Hz, 2H), 6.32 (d, J=16.2 Hz, 1H), 6.18 (d, J=16.2 Hz, 1H), 3.79 (s, 3H), 2.41 (s, 2H), 1.25 (s, 6H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 178.3, 159.1, 136.6, 130.5, 127.5, 126.0, 114.1, 55.5, 47.2, 35.8, 27.6 ppm. MS (ESI, m/z): Calculated for [C 14 H 18 3 ] (M+K) found (E)-5-(3-methoxyphenyl)pent-4-enoic acid (1e) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.22(t, J=7.9 Hz, 1H), 6.96 (d, J=7.5 Hz, 1H), 6.89 (s, 1H), 6.79 (d, J=8.0 Hz, 1H), 6.45 (d, J=15.8 Hz, 1H), (m, 1H), 3.82 (s, 3H), 2.56 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.4, 160.0, 138.9, 131.3, 129.7, 128.6, 119.0, 113.1, 111.6, 55.4, 33.9, 28.1 ppm. MS (ESI, m/z): Calculated for [C 12 H 14 3 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 1 and (E:Z=1:1)-5-(2-methoxyphenyl)pent-4-enoic acid (1f) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.42 (dd, J=7.6 Hz, 1H), 7.21 (t, J= 7.8 Hz, 2H), 7.15 (d, J=7.4 Hz, 1H), (m, 2H), 6.87 (d, J=8.2 Hz, 2H), 6.80 (d, J=15.8 Hz, 1H), (m, 1H), (m, 1H), (m, 1H), 3.85 (s, 3H), 3.83 (s, 3H), 3,40 (d, J=6.7 Hz, 2H), 3.12 (dd, J=6.9 Hz, 2H), 2.56 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.7, 178.7, 157.4, 156.6, 133.5, 129.9, 128.9, 128.7, 128.4, 127.6, 126.8, 126.6, 126.1, 122.1, 120.8, 120.7, 111.0, 110.5, 55.6, 55.5, 38.0, 34.1, 33.2, 28.5 ppm. MS (ESI, m/z): Calculated for [C 12 H 14 3 ] (M+K) found (E)-5-(benzo[d][1,3]dioxol-5-yl)pent-4-enoic acid (1g) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 6.89 (s, 1H), (m, 2H), 6.38 (d, 10 1g H

11 J=15.6 Hz, 1H), (m, 1H), 5.94 (s, 2H), 2.53 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.6, 148.2, 147.1, 132.0, 131.0, 126.4, 120.8, 108.4, 105.7, 101.2, 34.1, 28.0 ppm. MS (ESI, m/z): Calculated for [C 12 H 12 4 ] (M+H) found Characterization data obtained for 2a matched those previously reported in the literature. 2 (E)-5-(p-tolyl) pent-4-enoic acid (1h) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.26 (d, J=8.1 Hz, 2H), 7.12 (d, J=7.9 Hz, 2H), 6.44 (d, J=15.8 Hz, 1H), (m, 1H), 2.55 (s, 4H), 2.33 (s, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.4, 137.2, 134.7, 131.2, 129.4, 127.1, 126.2, 34.0, 28.1, 21.4 ppm. MS (ESI, m/z): Calculated for [C 12 H 14 2 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 1 (E)-5-(4-(tert-butyl)phenyl)pent-4-enoic acid (1i) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.35 (d, J=8.4 Hz, 2H), 7.30 (d, J=8.4 Hz, 2H), 6.46 (d, J=15.8 Hz, 1H), (m, 1H), 2.54 (s, 4H), 1.32 (s 9H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.5, 150.5, 134.7, 131.1, 127.4, 126.0, 125.6, 34.7, 34.1, 31.5, 28.1 ppm. MS (ESI, m/z): Calculated for [C 15 H 20 2 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 1 Cl (E)-5-(4-chlorophenyl)pent-4-enoic acid (1j) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.28 (s, 4H), 6.44 (d, J=15.8 Hz, 1H), (m, 1H), 2.57 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.4, 135.9, 133.0, 130.3, 128.9, 128.8, 127.5, 33.8, 28.0 ppm. MS (ESI, m/z): Calculated for [C 11 H 11 Cl 2 ] (M+H) found Characterization data obtained for 2a matched those previously reported in the literature. 1 1j H 11

12 (E)-5-(4-fluorophenyl)pent-4-enoic acid (1k) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ (brs, 1H), 7.29 (t, J=6.7 Hz, 2H), 6.98 (t, J=8.4 Hz, 2H), 6.42 (d, J=15.8 Hz, 1H), (m, 1H), 2.52 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.5, (d, J=244.5 Hz), (d, J=3.07 Hz), 130.2, 128.0, (d, J=7.8 Hz), (d, J=21.4 Hz), 34.1, 28.1 ppm. MS (ESI, m/z): Calculated for [C 11 H 11 F 2 ] (M-H) found Characterization data obtained for 2a matched those previously reported in the literature. 1 (E)-5-(4-(trifluoromethyl)phenyl)pent-4-enoic acid (1l) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.56 (d, J=8.2 Hz, 2H), 7.44 (d, J=8.2Hz, 2H), 6.50 (d, J=15.8 Hz, 1H), (m, 1H), 2.57 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.1, 150.5, 140.9, (q, J=73.3 Hz), (q, J=32.1 Hz), 128.9, 126.4, (q, J=3.8 Hz), (q, J=135.6 Hz), 33.7, 28.1 ppm. MS (ESI, m/z): Calculated for [C 12 H 11 F 3 2 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 3 (E)-5-phenylpent-4-enoic acid (1m) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.37 (d, J=7.7 Hz, 2H), 7.31 (t, J=8.1 Hz, 2H), 7.23 (t, J=7.1 Hz, 1H), 6.48 (d, J=15.8 Hz, 1H), (m, 1H), 2.56 (s, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.7, 137.4, 131.4, 128.7, 128.2, 127.4, 126.3, 34.0, 28.1 ppm. MS (ESI, m/z): Calculated for [C 11 H 12 2 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 1 (E)-5-(thiophen-2-yl)pent-4-enoic acid (1n) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.12 (d, J=5.0 Hz, 1H), (m, 1H), 6.90 (d, J=3.3 Hz, 1H), 6.60 (d, J=15.6 Hz, 1H), (m, 1H), 2.53 (s, 4H) 12

13 ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.2, 142.6, 128.0, 127.5, 125.1, 124.7, 123.8, 33.8, 27.9 ppm. MS (ESI, m/z): Calculated for [C 9 H 10 2 S] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature. 1 (E)-5-(thiophen-3-yl)pent-4-enoic acid (1o) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.26 (t, J=3.9 Hz, 1H), 7.20 (dd, J=5.0 Hz, 1H), 7.10 (d, J=2.1 Hz, 1H), 6.49 (d, J=15.7 Hz, 1H), (m, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 179.6, 140.1, 128.1, 126.1, 125.7, 125.1, 121.4, 34.0, 28.0 ppm. MS (ESI, m/z): Calculated for [C 9 H 10 2 S] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature Characterization data of the products. 5-(4-methoxybenzoyl)dihydrofuran-2(3H)-one (16.1 mg, 73%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.98 (d, J=8.9 Hz, 2H), 6.99 (d, J=8.9 Hz, 2H), 5.76 (dd, J=6.6 Hz, 1H), 3.90 (s, 3H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.9, 176.7, 164.6, 131.4, 126.7, 114.4, 78.3, 55.8, 27.1, 25.3 ppm. IR (thin film) ν max : 2924, 2371, 1775, 1683, 1599, 1445, 1245, 1074, 910, 734, 597 cm -1. MS (ESI, m/z): Calculated for [C 12 H 12 4 ] (M+Na) found Characterization data obtained for 2a matched those previously reported in the literature (4-methoxybenzoyl)-3-methyldihydrofuran-2(3H)-one (10 mg, 43%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.96 (d, J=8.7 Hz, 2H), 6.98 (d, J=8.6 Hz, 2H), 5.72 (d, J=9.0 Hz, 1H), 3.89 (s, 3H), (m, 2H), (m, 1H), 1.30 (d, J=6.6 Hz, 3Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.1, 179.3, 13

14 164.6, 131.4, 126.8, 114.4, 76.2, 55.8, 33.6, 32.8, 15.5 ppm. IR (thin film) ν max : 2975, 1779, 1685, 1601, 1513, 1254, 1234, 1171, 1012, 909, 733 cm -1. MS (ESI, m/z): Calculated for [C 13 H 14 4 ] (M+NH 4 ) found Isomer (2b ) (7.8 mg, 33%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.01 (d, J=8.9 Hz, 2H), 6.98 (d, J=8.9 Hz, 2H), 5.52 (dd, J=9.0 Hz, 1H), 3.89 (s, 3H), (m, 2H), (m, 1H), 1.33 (d, J=6.9 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.7, 178.6, 164.6, 131.6, 127.4, 114.3, 55.8, 34.9, 33.4, 15.7 ppm. IR (thin film) ν max : 2931, 1777, 1686, 1600, 1513, 1458, 1261, 1171, 1012, 914, 846 cm -1. MS (ESI, m/z): Calculated for [C 13 H 14 4 ] (M+NH 4 ) found (4-methoxybenzoyl)-4-methyldihydrofuran-2(3H)-one (9.8 mg, 42%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.95 (d, J=8.8 Hz, 2H), 6.98 (d, J=8.8 Hz, 2H), 5.32 (d, J=3.2 Hz, 1H), 3.88 (s, 3H), (m, 2H), (m, 1H), 1.32 (d, J=6.6 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.8, 176.2, 164.6, 131.3, 127.1, 114.4, 84.6, 55.8, 35.2, 33.4, 19.5 ppm. IR (thin film) ν max : 2968, 1787, 1682, 1601, 1513, 1423, 1266, 1171, 993, 942, 838 cm -1. MS (ESI, m/z): Calculated for [C 13 H 14 4 ] (M+H) found Isomer (2c ) (6.6 mg, 28%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.97 (d, J=8.9 Hz, 2H), 7.00 (d, J=8.9 Hz, 2H), 5.87 (d, J=7.6 Hz, 1H), 3.90 (s, 3H), (m, 1H), (m, 1H), (m, 1H), 0.94 (d, J=7 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.3, 176.3, 164.6, 130.9, 128.5, 114.5, 80.7, 55.8, 35.4, 34.5, 15.4 ppm. IR (thin film) ν max : 2969, 2932, 1784, 1678, 1601, 1513, 1423, 1238, 1165, 982, 941 cm -1. MS (ESI, m/z): Calculated for [C 13 H 14 4 ] (M+H) found (4-methoxybenzoyl)-4,4-dimethyldihydrofuran-2(3H)-one (17.6 mg, 71%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.95 (d, J=9.0 Hz, 2H), 7.00 (d, J=9.0 Hz, 2H), 5.47 (s, 1H), 3.90 (s, 3H), 2.62 (d, J=17.0 Hz, 1H), 2.33 (d, J=17.0 Hz, 1H), 1.38 (s, 3H), 0.98 (s, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 194.0, 176.1, 164.6, 131.2, 129.0, 114.5, 85.5, 55.8, 42.1, 40.8, 28.6, 23.7 ppm. IR (thin film) ν max : 2960, 2925, 1783, 1675, 1599, 1511, 1461, 1422, 1377, 1231, 990 cm -1. MS (ESI, m/z): Calculated for [C 14 H 16 4 ] (M+NH 4 ) found Characterization data obtained for 2d matched those previously reported in the literature. 5 14

15 5-(3-methoxybenzoyl)dihydrofuran-2(3H)-one (14.5 mg, 66%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ (m, 1H), 7.48 (t, J=2.0 Hz, 1H), 7.41 (t, J=8.1 Hz, 1H), (m, 1H), 5.79 (dd, J=8.4 Hz, 1H), 3.86 (s, 3H), (m, 3H), (m, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 194.4, 176.4, 160.3, 135.1, 130.2, 121.4, 120.9, 113.2, 78.4, 55.7, 27.0, 25.4 ppm. IR (thin film) ν max : 2943, 1784, 1696, 1598, 1483, 1432, 1269, 1167, 1044, 913, 732 cm -1. MS (ESI, m/z): Calculated for [C 12 H 12 4 ] (M+NH 4 ) found f 5-(2-methoxybenzoyl)dihydrofuran-2(3H)-one (9.9 mg, 45%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.87 (dd, J=7.8 Hz, 1H), (m, 1H), (m, 1H), 7.02 (d, J=8.3 Hz, 1H), (m, 1H), 3.95 (s, 3H), (m, 3H), (m, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 196.8, 177.3, 159.2, 135.4, 131.6, 124.4, 121.6, 111.9, 81.7, 56.0, 26.6, 25.4 ppm. IR (thin film) ν max : 2942, 1779, 1678, 1599, 1486, 1466, 1288, 1163, 1051, 927, 756 cm -1. MS (ESI, m/z): Calculated for [C 12 H 12 4 ] (M+Na) found Characterization data obtained for 2f matched those previously reported in the literature. 6 5-(benzo[d][1,3]dioxol-5-carbonyl)dihydrofuran-2(3H)-one (16.1 mg, 69%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.58 (dd, J=8.2 Hz, 1H), 7.44 (d, J=1.7 Hz, 1H), 6.90 (d, J=8.2 Hz, 1H), 6.08 (s, 2H), 5.72 (dd, J=7.8 Hz, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.5, 176.5, 153.0, 148.8, 128.5, 125.7, 108.6, 106.8, 102.4, 78.3, 27.1, 25.2 ppm. IR (thin film) ν max : 2918, 1781, 1684, 1604, 1504, 1490, 1447, 1254, 1177, 1037, 930 cm -1. MS (ESI, m/z): Calculated for [C 12 H 10 5 ] (M+NH 4 ) found

16 5-(4-methylbenzoyl)dihydrofuran-2(3H)-one (15.3 mg, 75%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.87 (d, J=8.2 Hz, 2H), 7.31 (d, J=8.0 Hz, 2H), 5.79 (dd, J=8.2 Hz, 1H), (m, 4H), 2.42 (s, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 194.1, 176.6, 145.6, 131.3, 129.9, 129.1, 126.2, 78.4, 27.0, 25.3, 22.0 ppm. IR (thin film) ν max : 2926, 2255, 1782, 1690, 1607, 1459, 1417, 1234, 1173, 912, 730 cm -1. MS (ESI, m/z): Calculated for [C 12 H 12 3 ] (M+K) found Characterization data obtained for 2h matched those previously reported in the literature. 4 5-(4-(tert-butyl)benzoyl)dihydrofuran-2(3H)-one (15.3 mg, 62%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.93 (d, J=8.5 Hz, 2H), 7.54 (d, J=8.5 Hz, 2H), (m, 1H), (m, 4H), 1.35 (s, 9H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 194.1, 176.5, 158.5, 131.3, 129.0, 126.2, 78.5, 35.5, 31.2, 27.1, 25.2 ppm. IR (thin film) ν max : 2963, 2367, 1785, 1690, 1605, 1412, 1235, 1171, 977, 927, 854 cm -1. MS (ESI, m/z): Calculated for [C 15 H 18 3 ] (M+Na) found Characterization data obtained for 2i matched those previously reported in the literature. 4 Cl. 2j 5-(4-chlorobenzoyl)dihydrofuran-2(3H)-one (17.5 mg, 78%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.95 (d, J=8.7 Hz, 2H), 7.50 (d, J=8.7 Hz, 2H), 5.71 (dd, J=7.8 Hz, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.4, 176.1, 141.2, 132.3, 130.5, 129.6, 78.5, 27.0, 24.8 ppm. IR (thin film) ν max : 2925, 1775, 1745, 1690, 1587, 1460, 1375, 1238, 1047, 976, 849 cm -1. MS (ESI, m/z): Calculated for [C 11 H 9 Cl 3 ] (M+NH 4 ) found Characterization data obtained for 2j matched those previously reported in the literature. 4 5-(4-fluorobenzoyl)dihydrofuran-2(3H)-one (14.8 mg, 71%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.04 (dd, J=8.9 Hz, 2H), 7.19 (t, J=8.6 Hz, 2H), 5.73 (dd, J=7.8 Hz, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 192.9, 176.2, (d, J=255.7 Hz), (d, J=9.6 Hz), 130.4, (d, J=21.9 Hz), 78.5, 27.1, 24.8 ppm. IR (thin film) ν max : 2923, 2852, 1746, 1701, 1597, 16

17 1460, 1376, 1236, 1159, 1046, 973 cm -1. MS (ESI, m/z): Calculated for [C 11 H 9 F 3 ] (M+Na) found Characterization data obtained for 2k matched those previously reported in the literature. 4 5-(4-(trifluoromethyl)benzoyl)dihydrofuran-2(3H)-one (6.5 mg, 25%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.13 (d, J=8.3 Hz, 2H), 7.8 (d, J=8.3 Hz, 2H), 5.75 (dd, J=7.7 Hz, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.8, 175.9, (q, J=80.6 Hz), 135.5, 129.6, (q, J=3.7 Hz), (q, J=271.1 Hz), 78.7, 27.0, 24.6 ppm. IR (thin film) ν max : 2924, 1786, 1702, 1514, 1413, 1328, 1171, 1133, 1067, 977, 858 cm -1. MS (ESI, m/z): Calculated for [C 12 H 9 F 3 3 ] (M+K) found benzoyldihydrofuran-2(3H)-one (14.3 mg, 75%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.98 (d, J=7.3 Hz, 2H), 7.63 (t, J=7.4 Hz, 1H), 7.51 (t, J=7. Hz, 2H), 5.81 (dd, J=8.3 Hz, 1H), (m, 3H), (m, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 194.5, 176.4, 134.5, 133.8, 129.2, 129.0, 78.4, 27.0, 25.2 ppm. IR (thin film) ν max : 2935, 2255, 1779, 1697, 1597, 1450, 1377, 1174, 1066, 916, 733 cm -1. MS (ESI, m/z): Calculated for [C 11 H 10 3 ] (M+NH 4 ) found Characterization data obtained for 2m matched those previously reported in the literature. 4 S 2n 5-(thiophene-2-carbonyl)dihydrofuran-2(3H)-one (14.9 mg, 76%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.92 (dd, J=3.9 Hz, 1H), 7.77(dd, J=5.0 Hz, 1H), 7,20 (dd, J=4.9 Hz, 1H), (m, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 188.1, 176.3, 140.4, 135.9, 134.3, 128.9, 79.6, 27.1, 25.5 ppm. IR (thin film) ν max : 3464, 2927, 1780, 1668, 1517, 1414, 1242, 1169, 1052, 902, 733 cm -1. MS (ESI, m/z): Calculated for [C 9 H 8 3 S] (M+K) found Characterization data obtained for 2n matched those previously reported in the literature. 7 17

18 5-(thiophene-3-carbonyl)dihydrofuran-2(3H)-one (13.1 mg, 67%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.28 (dd, J=2.8 Hz, 1H), 7.62 (dd, J=5.1 Hz, 1H), 7.39 (dd, J=5.1 Hz, 1H), (m, 1H), (m, 4H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 189.2, 176.3, 138.7, 134.7, 127.5, 127.1, 79.9, 27.1, 25.1 ppm. IR (thin film) ν max : 2923, 1775, 1686, 1509, 1459, 1419, 1236, 1152, 1068, 809, 704 cm -1. MS (ESI, m/z): Calculated for [C 9 H 8 3 S] (M+NH 4 ) found oxo-1-phenylpropan-2-yl 4-bromobenzoate (34.5 mg, 52%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.0 (d, J=7.5 Hz, 2H), 7.96 (d, J=8.5 Hz, 2H), 7.60 (t, J=8.4 Hz, 3H), 7.49 (t, J=7.7 Hz, 2H), 6.21 (q, J=7.0 Hz, 1H), 1.68 (d, J=7.0 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 196.7, 165.5, 134.5, 133.9, 132.0, 131.6, 129.1, 128.7, 128.6, 72.3, 17.4 ppm. IR (thin film) ν max : 3407, 1692, 1589, 1450, 1276, 1228, 1120, 1012, 858, 756, 701 cm -1. MS (ESI, m/z): Calculated for [C 16 H 13 Br 3 ] (M+Na) found Characterization data obtained for 5aa matched those previously reported in the literature. 8 Br. 5ba 1-(4-methoxyphenyl)-1-oxopropan-2-yl 4-bromobenzoate (34.8 mg, 48%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.99 (d, J=8.9 Hz, 2H), 7.96 (d, J=8.6 Hz, 2H),7.60 (d, J=8.5 Hz, 2H), 6.97 (d, J=8.9 Hz, 2H), 6.17 (dd, J=7.0 Hz, 1H), 3.88 (s, 3H), 1.67 (d, J=7.0 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 195.0, 165.5, 164.2, 132.0, 131.6, 131.1, 128.7, 128.6, 127.4, 114.3, 72.1, 55.7, 17.6 ppm. IR (thin film) ν max : 1716, 1686, 1600, 1275, 1236, 1177, 1120, 1027, 965, 847, 754 cm -1. MS (ESI, m/z): Calculated for [C 17 H 15 Br 4 ] (M+H) found Br Ph 5ca 18

19 2-oxo-1,2-diphenylethyl 4-bromobenzoate (28.4 mg, 36%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ (m, 4H), 7.59 (dd, J=6.8 Hz, 2H), 7.56 (dd, J=7.9 Hz, 2H), 7.54 (d, J=7.4 Hz, 1H), 7.44 (d, J=8.0 Hz, 2H), (m, 3H), 7.08 (s, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.6, 165.5, 134.8, 133.8, 133.7, 132.0, 131.7, 129.7, 129.4, 129.3, 129.1, 129.0, 128.9, 128.8, 128.5, 78.4 ppm. IR (thin film) ν max : 2925, 1722, 1697, 1591, 1278, 1174, 1101, 1012, 908, 756, 697 cm -1. MS (ESI, m/z): Calculated for [C 21 H 15 Br 3 ] (M+H) found Characterization data obtained for 5ca matched those previously reported in the literature. 9 1-oxo-2,3-dihydro-1H-inden-2-yl 4-bromobenzoate (29.0 mg, 44%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ (dd, J=6.8 Hz, 2H), 7.85 (d, J=7.7 Hz, 1H), (m, 1H), 7.61 (d, J=8.6 Hz, 2H), 7.50 (d, J=7.7 Hz, 1H), 7.45 (t, J=7.5 Hz, 1H), 5.64 (dd, J=8.0 Hz, 1H), 3.78 (dd, J=17.0 Hz, 1H), 3.21 (dd, J=17.0 Hz, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 200.4, 165.6, 150.6, 136.2, 134.8, 132.0, 131.7, 128.9, 128.5, 126.9, 124.8, 74.9, 33.8 ppm. IR (thin film) ν max : 3416, 1718, 1587, 1467, 1397, 1263, 1121, 1007, 904, 845, 747 cm -1. MS (ESI, m/z): Calculated for [C 16 H 11 Br 3 ] (M+H) found Br 5ea 1-oxo-1,2,3,4-tetrahydronaphthalen-2-yl 4-bromobenzoate (28.9 mg, 42%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.06 (dd, J=7.9 Hz, 1H), 8.01 (d, J=8.7 Hz, 2H), 7.62 (d, J=8.6 Hz, 2H), (m, 1H), 7.36 (t, J=7.6 Hz, 1H), 7.31 (d, J=7.7 Hz, 1H), 5.79 (dd, J=13.3 Hz, 1H), (m, 1H), (m, 1H), (m, 1H), (m, 1H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 193.0, 165.3, 143.3, 134.3, 132.0, 131.8, 131.7, 128.9, 128.6, 128.1, 127.3, 75.5, 29.5, 28.2 ppm. IR (thin film) ν max : 2932, 1725, 1591, 1484, 1265, 1173, 1124, 1012, 910, 847, 747 cm -1. MS (ESI, m/z): Calculated for [C 17 H 13 Br 3 ] (M+H) found oxo-1-phenylpropan-2-yl benzoate (21.3 mg, 42%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ (d, J=7.1 Hz, 2H), 8.02 (d, J=7.2 Hz, 19

20 2H), 7.60 (q, J=7.4 Hz, 2H), (m, 4H), 6.22 (q, J=7.0 Hz, 1H), 1.69 (d, J=7.0 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 196.9, 166.2, 134.7, 133.8, 133.5, 130.1, 129.7, 129.0, 128.7, 128.6, 72.1, 17.4 ppm. IR (thin film) ν max : 2981, 1721, 1692, 1596, 1451, 1275, 1118, 1031, 968, 790, 704 cm -1. MS (ESI, m/z): Calculated for [C 16 H 14 3 ] (M+Na) found Characterization data obtained for 5ab matched those previously reported in the literature. 8 5ac 1-oxo-1-phenylpropan-2-yl 4-methoxybenzoate (22.7 mg, 40%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.05 (dd, J=6.9 Hz, 2H), (m, 2H), (m, 1H), 7.48 (t, J=7.6 Hz, 2H), 6.93 (dd, J=6.9 Hz, 2H), 6.18 (q, J=7.0 Hz, 1H), 3.86 (s, 3H), 1.66 (d, J=7.0 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 197.2, 165.9, 163.9, 134.8, 133.7, 132.2, 129.0, 128.8, 122.1, 113.9, 71.8, 55.7, 17.4 ppm. IR (thin film) ν max : 2932, 1690, 1604, 1510, 1254, 1171, 1116, 1031, 849, 733, 698 cm -1. MS (ESI, m/z): Calculated for [C 17 H 16 4 ] (M+H) found Characterization data obtained for 5ac matched those previously reported in the literature. 8 1-oxo-1-phenylpropan-2-yl furan-2-carboxylate (14.6 mg, 30%) White solid. 1 H NMR (400 MHz, CDCl 3 ): δ 8.01 (d, J=7.2 Hz, 2H), 7.63 (t, J=7.4 Hz, 2H), 7.51 (t, J=7.6 Hz, 2H), 7.29 (s, 1H), 6.55 (dd, J=3.4 Hz, 1H), 6.22 (q, J=7.1 Hz, 1H), 1.69 (d, J=6.8 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 196.5, 158.1, 147.0, 144.3, 134.5, 133.9, 129.0, 128.8, 119.1, 112.2, 72.0, 17.5 ppm. IR (thin film) ν max : 1698, 1580, 1474, 1397, 1289, 1229, 1180, 1120, 970, 765, 701 cm -1. MS (ESI, m/z): Calculated for [C 14 H 12 4 ] (M+H) found S 5ae 1-oxo-1-phenylpropan-2-yl thiophene-2-carboxylate (19.2 mg, 37%) Colourless liquid. 1 H NMR (400 MHz, CDCl 3 ): δ 6.02 (d, J=7.2 Hz, 2H), 7.89 (d, J=2.8 Hz, 1H), (m, 2H), 7.51 (t, J=7.6 Hz, 2H), 7.13 (t, J=4.4 Hz, 1H), 6.19 (q, J=7.1 Hz, 1H), 1.69 (d, J=7.2 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 20

21 196.7, 161.8, 134.6, 134.4, 133.8, 133.2, 133.1, 129.0, 128.8, 128.0, 72.3, 17.4 ppm. IR (thin film) ν max : 1696, 1525, 1450, 1417, 1364, 1262, 1227, 1100, 968, 747, 700 cm -1. MS (ESI, m/z): Calculated for [C 14 H 12 3 S] (M+K) found Characterization data obtained for 5ae matched those previously reported in the literature oxo-1-phenylpropan-2-yl acetate (9.6 mg, 25%) Colourless liquid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.95 (dd, J=8.4 Hz, 2H), (m, 1H), 7.48 (t, J=7.6 Hz, 2H), 5.98 (q, J=7.0 Hz, 1H), 2.15 (s, 3H), 1.54 (d, J=7.0 Hz, 3H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ 197.1, 170.6, 134.6, 133.8, 129.0, 128.7, 71.6, 21.0, 17.4 ppm. IR (thin film) ν max : 1743, 1670, 1597, 1450, 1372, 1233, 1091, 1040, 973, 733, 701 cm -1. MS (ESI, m/z): Calculated for [C 11 H 12 3 ] (M+Na) found Characterization data obtained for 5af matched those previously reported in the literature References (1) Tan, C. K.; Zhou, L.; Yeung, Y. Y. rg. Lett. 2011, 13, (2) Anuradha, V.; Srinivas, P. V.; Rao, J. M. Natural Product Research. 2004, 18, 247. (3) Wardrop, D. J.; Bowen, E. G.; Forslund, R. E.; Sussman, A. D.; Weerasekera, S. L. J. Am. Chem. Soc. 2010, 132, (4) Tada, N.; Cui, L.; Ishigami, T.; Ban, K.; Miura, T.; Uno, B.; Itoh, A. Green Chem. 2012, 14, (5) Armstrong, A.; Ashraff, C.; Chung, H.; Murtagh, L. Tetrahedron. 2009, 65, (6) Uyanik, M.; Suzuki, D.; Yasui, T.; Ishihara, K. Angew. Chem. Int. Ed. 2011, 50, (7) Tellitu, I.; Serna, S.; Herrero, M. T.; Moreno, I.; Domínguez, E.; SanMartin, R. J. rg. Chem. 2007, 72, (8) Li, C. L.; Jin, T.; Zhang, X. L.; Li, C. J.; Jia, X. S.; Li, J. rg. Lett. 2016,18, (9) Zhou, Z.; Cheng, J.; Yu, J. T. rg. Biomol. Chem. 2015, 13, (10) Zhu, F.; Wang, Z.; X. Tetrahedron 2014, 70, (11) Jiang, T.; Quan, X.; Zhu, C.; Andersson, P.; G.; Bäckvall, J. E. Angew.Chem.Int. Ed. 2016, 55, (12) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Scalmani, G.; Barone, V.; Mennucci, B.;. Petersson, G. A.; Nakatsuji, H.; Caricato, M.; Li, X.; Hratchian, H. P.; Izmaylov, A. F.; Bloino, J.; Zheng, G.; Sonnenberg, J. L.; Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.; Nakajima, T.; Honda, Y.; Kitao,.; Nakai, H.; Vreven, T.; Montgomery, J. A.; Peralta, J. E.; gliaro, F.; Bearpark, M.; Heyd, J. J.; Brothers, E.; 21

22 Kudin, K. N.; Staroverov, V. N.; Kobayashi, R.; Normand, J.; Raghavachari, K.; Rendell, A.; Burant, J. C.; Iyengar, S. S.; Tomasi, J.; Cossi, M.; Rega, N.; Millam, N. J.; Klene, M.; Knox, J. E.; Cross, J. B.; Bakken, V.; Adamo, C.; Jaramillo, J.; Gomperts, R.; Stratmann, R. E.; Yazyev,.; Austin, A. J.; Cammi, R.; Pomelli, C.; chterski, J. W.; Martin, R. L.; Morokuma, K.; Zakrzewski, V. G.; Voth, G. A.; Salvador, P.; Dannenberg, J. J.; Dapprich, S.; Daniels, A. D.; Farkas,.; Foresman, J. B.; rtiz, J. V.; Cioslowski, J.; D.J. Fox, R. Gaussian 09, A. 02, Gaussian, Inc.: Wallingford CT, NMR Spectra. 22

23 7.1 NMR Spectra of the substrates. 23

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38 7.2 NMR Spectra of the products. 38

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