Supplementary Material Control experiments S2 Characterization data for the products S2-S7 References S8 MR spectra for the products S9-S28 S1
Control experiments 2a (99.5 mg, 0.5 mmol), I 2 (50.8 mg, 0.2 mmol), DMA (2 ml) and TBHP (70 % aqueous solution, 1 mmol) were placed in a tube (10 ml) and sealed with a thin film. Then the reaction mixture was stirred at 25 C for 4 h, heated up to 60 C and stirred at this temperature. We detected the mixture at different heating time, and benzoylformaldehyde was not detected by GC with mesitylene as internal standard. 1a (105.8 mg, 0.7 mmol), 2a (99.5 mg, 0.5 mmol), I 2 (50.8 mg, 0.2 mmol), DMA (2 ml), TBHP (70 % aqueous solution, 1 mmol) and radical scavenger (1 mmol) were placed in a tube (10 ml) and sealed with a thin film. Then the reaction mixture was stirred at 25 C for 4 h, heated up to 60 C and stirred at this temperature for another 4 h. After that, the resulting mixture was cooled to the room temperature, filtered through thin layer silica gel column. The yield of 3a was determined by GC with mesitylene as an internal standard. Characterization data for the products 2,5-diphenyloxazole (3a) [1] ether:ethyl acetate = 10:1) to give light yellow solid (154.7 mg, 70%), mp = 70-72 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.12-8.09 (m, 2 H), 7.72-7.69 (m, 2 H), 7.50-7.40 (m, 6 H), 7.35-7.24 (m, 1 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.3, 151.4, 130.4, 129.0, 128.9, 128.5, 128.1, 127.6, 126.4, 124.3, 123.6. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 15 H 12 : 222.0913, Found: 222.0911. 5-phenyloxazole (3b) [2] S2
ether:ethyl acetate = 10:1) to give light yellow solid (74.0 mg, 51%), mp = 39-41 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.91 (s, 1 H), 7.67 (q, 2 H), 7.45-7.40 (m, 2 H), 7.35-7.31 (m, 2 H). 13 C MR (75 MHz, CDCl 3 ): δ 151.7, 150.6, 129.1, 128.8, 127,9, 124.5, 121.6. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 9 H 8 : 146.0600, Found: 146.0604. 2-methyl-5-phenyloxazole (3c) [3] ether:ethyl acetate = 10:1) to give light yellow solid (101.8 mg, 64%), mp = 57-59 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.61 (t, 2 H), 7.40 (q, 2 H), 7.31 (d, 1 H), 5.70 (s, 1 H), 2.52 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.2, 151.3, 129.0, 128.4, 128.2, 124.3, 124.1, 122.0, 14.2. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 10 H 10 : 160.0757, Found: 160.0755. 5-phenyl-2-propyloxazole (3d) [4] ether:ethyl acetate = 10:1) to give light yellow solid (114.1 mg, 61%), mp = 65-67 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.73-7.64 (m, 2 H), 7.50 (s, 1 H), 7.48-7.34 (m, 3 H), 2.88-2.82 (m, 2 H), 1.90-1.78 (m, 2 H), 1.05 (t, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 158.0, 153.6, 136.0, 133.6, 132.2, 129.0, 128.8, 125.3, 35.9, 19.5, 13.9. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 12 H 14 : 188.1070, Found: 188.1068. 2-isopropyl-5-phenyloxazole (3e) [4] ether:ethyl acetate = 10:1) to give oil (97.3 mg, 52%). 1 H MR (300 MHz, CDCl 3 ): δ 7.63-7.59 (m, 2 H), 7.43-7.37 (m, 2 H), 7.32-7.27 (m, 1 H), 7.21 (s, 1 H), 3.15 (m, Ј = 9 Hz, 1 H), 1.42-1.26 (m, Ј = 9 Hz, 6 H). 13 C MR (75 MHz, CDCl 3 ): δ 168.8, 150.8, 128.9, 128.5, 128.2, 124.1, 121.7, 28.7, 20.6. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 12 H 14 : 188.1070, Found: 188.1068. 2-(sec-butyl)-5-phenyloxazole (3f) ether:ethyl acetate = 10:1) to give oil (100.6 mg, 50%). 1 H MR (300 MHz, CDCl 3 ): δ 7.63-7.25 (m, 5 H), 7.22 (s, 1 H), 2.95 (m, Ј = 4 Hz, Ј = 6 Hz, 1 H), 1.86 (m, Ј = 4 Hz, Ј = 6 Hz, Ј = 6 Hz, 1 H), 1.73 (m, Ј = 4 Hz, Ј S3
= 6 Hz, Ј = 6 Hz, 1 H), 1.38 (d, Ј = 4 Hz, 3 H), 0.95 (t, Ј = 4 Hz, Ј = 6 Hz, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 168.1, 150.1, 129.2, 128.9, 128.5, 128.1, 124.1, 121.7, 35.5, 28.3, 18.1, 11.7. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 13 H 16 : 202.1226, Found: 202.1230. 2-isobutyl-5-phenyloxazole (3g) ether:ethyl acetate = 10:1) to give light yellow solid (114.6 mg, 57%), mp = 54-56 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.62-7.58 (m, 2 H), 7.41-7.36 (m, 2 H), 7.31-7.26 (m, 1 H), 7.22 (s, 1 H), 2.70 (d, Ј = 6 Hz, 2 H), 2.25-2.16 (m, Ј = 6 Hz, Ј = 6 Hz, 1 H), 1.02 (d, Ј = 6 Hz, 6 H). 13 C MR (75 MHz, CDCl 3 ): δ 164.1, 150.9, 128.9, 128.4, 128.1, 124.0, 121.8, 37.3, 27.7, 22.4. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 13 H 16 : 202.1026, Found: 202.1030. 2-benzyl-5-phenyloxazole (3h) [3] ether:ethyl acetate = 10:1) to give light yellow solid (87.0 mg, 37%), mp = 50-52 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.69-7.65 (m, 2 H), 7.62 (s, 1 H), 7.53-7.22 (m, 8 H), 4.17 (s, 2 H). 13 C MR (75 MHz, CDCl 3 ): δ 156.3, 153.3, 136.6, 135.6, 132.4, 129.7, 129.0, 128.9, 128.7, 127.2, 125.3, 40.5. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 14 : 236.1070, Found: 236.1068. 5-(4-chlorophenyl)-2-phenyloxazole (3i) [5] Cl ether:ethyl acetate = 10:1) to give light yellow (168.3 mg, 66%), mp = 95-97 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.12-8.09 (m, 2 H), 7.66 (d, 2 H), 7.49-7.41 (m, 6 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.5, 150.4, 134.3, 130.6, 129.6, 129.0, 127.4, 126.7, 126.5, 125.5, 124.0. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 15 H 11 Cl: 256.0524, Found: 256.0526. 5-(4-bromophenyl)-2-phenyloxazole (3j) [5] Br ether:ethyl acetate = 10:1) to give light yellow solid (191.4 mg, 64%), mp = 98-100 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.12-8.07 (m, 2 H), 7.61-7.52 (m, 4 H), 7.51-7.45 (m, 4 H). 13 C MR (75 MHz, CDCl 3 ): δ S4
161.6, 150.4, 132.3, 130.6, 129.0, 127.4, 126.5, 125.7, 124.1, 122.4. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 15 H 11 Br: 300.0019, Found: 300.0015. 2-phenyl-5-(p-tolyl)oxazole (3k) [5] ether:ethyl acetate = 10:1) to give light yellow solid (119.9 mg, 51%), mp = 76-78 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.11 (t, 2 H), 7.62 (d, 2 H), 7.51-7.46 (m, 3 H), 7.39 (s, 1 H), 7.30-7.24 (m, 2 H), 2.42 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.0, 151.6, 138.6, 130.3, 129.7, 128.9, 127.7, 126.4, 125.5, 124.3, 123.0, 21.5. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 14 : 236.1070, Found: 236.1068. 5-(4-methoxyphenyl)-2-phenyloxazole (3l) [5] Synthesized according to typical procedure and purified by column chromatography (petroleum ether:ethyl acetate = 10:1) to give light yellow solid (118.0 mg, 51%), mp = 80-81 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.11-8.08 (m, 2 H), 7.65 (t, 2 H), 7.50-7.42 (m, 3 H), 7.32 (s, 1 H), 6.99-6.92 (m, 2 H), 3.86 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 160.6, 159.9, 151.4, 130.6, 130.1, 128.8, 127.6, 126.2, 125.8, 122.0, 121.0, 114.4, 113.7, 55.4. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 14 2 : 252.1019, Found: 252.1016. 5-([1,1'-biphenyl]-4-yl)-2-phenyloxazole (3m) [3] Synthesized according to typical procedure and purified by column chromatography (petroleum ether:ethyl acetate = 10:1) to give light yellow solid (148.6 mg, 50%), mp = 150-152 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.15-8.13 (m, 2 H), 8.12-7.19 (m, 2 H), 7.74-7.60 (m, 4 H), 7.54-7.45 (m, 6 H), 7.40-7.35 (m, 1 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.2, 151.1, 141.2, 140.3, 130.4, 128.9, 128.8, 127.7, 127.6, 127.5, 127.3, 127.0, 126.3, 124.6, 123.6. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 21 H 16 : 298.1226, Found: 298.1226. 2-phenyl-5-(4-(trifluoromethyl)phenyl)oxazole (3n) [6] Synthesized according to typical procedure and purified by column chromatography F 3 C (petroleum ether:ethyl acetate = 10:1) to give light yellow solid (185.0 mg, 64%), mp = 98-100 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.13-8.10 (m, 2 H), 7.82 (d, 2 H), 7.69 (d, 2 H), 7.55 (s, 1 H), 7.53-7.45 (m, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.2, 150.0, 131.4, 130.2 (q, J = 32.4 Hz), 129.0, 127.2, 126.6, 126.1 (q, J = 3.8 Hz), S5
125.4, 124.4, 124.1 (q, J = 270.3 Hz). HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 11 F 3 : 290.0787, Found: 290.0785. 5-(2-chlorophenyl)-2-phenyloxazole (3o) [7] ether:ethyl acetate = 10:1) to give light yellow solid (140.3 mg, 55%), mp = 76-78 C. 1 H MR Cl (300 MHz, CDCl 3 ): δ 8.15-8.12 (m, 2 H), 7.94-7.88 (m, 2 H), 7.50-7.48 (m, 4 H), 7.44-7.36 (m, 1 H), 7.30-7.27 (m, 1 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.1, 147.9, 130.9, 130.8, 130.7, 129.0, 129.9, 128.6, 127.8, 127.4, 127.2, 127.0, 126.6. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 15 H 11 Cl: 256.0524, Found: 256.0522. 2-phenyl-5-(o-tolyl)oxazole (3p) [6] ether:ethyl acetate = 10:1) to give light yellow solid (101.1 mg, 43%), mp = 62-64 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.13-8.10 (m, 2 H), 7.79 (t, 1 H), 7.51-7.45 (m, 3 H), 7.35 (s, 1 H), 7.31-7.25 (m, 3 H), 2.54 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 161.0, 150.9, 135.1, 131.4, 130.5, 129.0, 128.6, 127.7, 127.5, 127.0, 126.5, 126.4, 126.4, 22.0. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 14 : 236.1070, Found: 236.1068. 4-methyl-2,5-diphenyloxazole (3q) [6] ether:ethyl acetate = 10:1) to give light yellow solid (129.3 mg, 55%), mp = 78-80 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.37 (s, 2H), 7.65-7.46 (m, 8 H), 2.43 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 153.5, 149.0, 146.9, 135.7, 134.2, 131.2, 131.0, 129.0, 128.9, 128.6, 128.4, 18.1. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 16 H 14 : 236.1070, Found: 236.1068. 2-benzyl-4-methyl-5-phenyloxazole (3r) ether:ethyl acetate = 10:1) to give light yellow solid (87.2 mg, 35%), mp = 58-60 C. 1 H MR (300 S6
MHz, CDCl 3 ): δ 7.49-7.37 (m, 7 H), 7.34-7.30 (m, 2 H), 7.23 (d, 1 H), 4.12 (s, 2 H), 2.32 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 154.3, 153.0, 148.7, 136.2, 135.6, 130.4, 129.6, 128.9, 128.7, 128.6, 128.4, 127.0, 40.4, 17.9. HRMS (APCI- FTMS) m/z: [M + H] + calcd for C 17 H 16 : 250.1226, Found: 250.1224. 2,4-dimethyl-5-phenyloxazole (3s) [8] ether:ethyl acetate = 10:1) to give light yellow solid (103.8 mg, 60%), mp = 42-44 C. 1 H MR (300 MHz, CDCl 3 ): δ 7.48-7.35 (m, 5 H), 2.47 (s, 3 H), 2.32 (s, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 154.7, 151.8, 148.0, 135.6, 130.2, 128.8, 128.6, 128.3, 20.5, 17.8. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 11 H 12 : 174.0913, Found: 174.0915. 2-phenyl-5-(pyridin-4-yl)oxazole (3t) [9] ether:ethyl acetate = 5:1) to give light yellow solid (115.5 mg, 52%), mp = 110-112 C. 1 H MR (300 MHz, CDCl 3 ): δ 8.69 (s, 2 H), 8.15-8.12 (m, 2 H), 7.66 (s, 1 H), 7,59 (d, 2 H), 7,51 (t, 3 H). 13 C MR (75 MHz, CDCl 3 ): δ 162.7, 150.6, 148.8, 135.0, 131.1, 129.1, 127.1, 127.0, 126.7, 118.1. HRMS (APCI-FTMS) m/z: [M + H] + calcd for C 14 H 11 2 : 223.0866, Found: 223.0864. S7
References 1. Wan C, Gao L, Wang Q, Zhang J, Wang Z: Simple and Efficient Preparation of 2,5-Disubstituted xazoles via a Metal-Free-Catalyzed Cascade Cyclization. rg Lett 2010, 12:3902-3905. 2. Besselievre F, Mahuteau-Betzer F, Grierson DS, Piguel S: Ligandless Microwave-Assisted Pd/Cu-Catalyzed Direct Arylation of xazoles. J rg Chem 2008, 73:3278-3280. 3. Keni M, Tepe JJ: ne-pot Friedel Crafts/Robinson Gabriel Synthesis of xazoles Using xazolone Templates. J rg Chem 2005, 70:4211-4213. 4. Kawano Y, Togo H: Iodoarene-catalyzed one-pot preparation of 2,4,5-trisubstituted oxazoles from alkyl aryl ketones with mcpba in nitriles. Tetrahedron 2009, 65:6251-6256. 5. Jiang H, Huang H, Cao H, Qi C: TBHP/I-2-Mediated Domino xidative Cyclization for ne-pot Synthesis of Polysubstituted xazoles. rg Lett 2010, 12:5561-5563. 6. hnmacht SA, Mamone P, Culshaw AJ, Greaney MF: Direct arylations on water: synthesis of 2,5-disubstituted oxazoles balsoxin and texaline. Chem Commun 2008:1241-1243. 7. Lee JJ, Kim J, Jun YM, Lee BM, Kim BH: Indium-mediated one-pot synthesis of benzoxazoles or oxazoles from 2-nitrophenols or 1-aryl-2-nitroethanones. Tetrahedron 2009, 65:8821-8831. 8. Ishiwata Y, Togo H: Iodoarene-mediated one-pot preparation of 2,5-disubstituted and 2,4,5-trisubstituted oxazoles from alkyl aryl ketones with oxone in nitriles. Tetrahedron 2009, 65:10720-10724. 9. Zhang F, Greaney MF: Decarboxylative Cross-Coupling of Azoyl Carboxylic Acids with Aryl Halides. rg Lett 2010, 12:4745-4747. S8
MR spectra for the products 2,5-diphenyloxazole (3a) S9
5-phenyloxazole (3b) S10
2-methyl-5-phenyloxazole (3c) S11
5-phenyl-2-propyloxazole (3d) S12
2-isopropyl-5-phenyloxazole (3e) S13
2-(sec-butyl)-5-phenyloxazole (3f) S14
2-isobutyl-5-phenyloxazole (3g) S15
2-benzyl-5-phenyloxazole (3h) S16
5-(4-chlorophenyl)-2-phenyloxazole (3i) S17
5-(4-bromophenyl)-2-phenyloxazole (3j) S18
2-phenyl-5-(p-tolyl)oxazole (3k) S19
5-(4-methoxyphenyl)-2-phenyloxazole (3l) S20
5-([1,1'-biphenyl]-4-yl)-2-phenyloxazole (3m) S21
2-phenyl-5-(4-(trifluoromethyl)phenyl)oxazole (3n) S22
5-(2-chlorophenyl)-2-phenyloxazole (3o) S23
2-phenyl-5-(o-tolyl)oxazole (3p) S24
4-methyl-2,5-diphenyloxazole (3q) S25
2-benzyl-4-methyl-5-phenyloxazole (3r) S26
2,4-dimethyl-5-phenyloxazole (3s) S27
2-phenyl-5-(pyridin-4-yl)oxazole (3t) S28