Dimethylformamide → Methyl 2-chloro-1,3-benzoxazole-7-carboxylate

반응식

[CH3:1][O:2][C:3]([C:5]1[C:13]2[O:12][C:11](S)=[N:10][C:9]=2[CH:8]=[CH:7][CH:6]=1)=[O:4].S(Cl)([Cl:17])=O.CN(C=O)C>>[CH3:1][O:2][C:3]([C:5]1[C:13]2[O:12][C:11]([Cl:17])=[N:10][C:9]=2[CH:8]=[CH:7][CH:6]=1)=[O:4]

참가 물질

반응물 3

HCID 6228Dimethylformamide

HCID 24386Thionyl Chloride

HCID 178497587HCID 178497587, 화합물

생성물 1

HCID 68406054Methyl 2-chloro-1,3-benzoxazole-7-carboxylate수율 81%

실험 절차

To 2-mercapto-benzooxazole-7-carboxylic acid methyl ester (1.0 g, 4.78 mmol, 1.0 equiv) was added thionyl chloride (8.0 g, 4.9 mL, 67.6 mmol, 14.0 equiv) and anhydrous DMF (0.4 g, 0.4 mL, 5.19 mmol, 1.1 equiv) and the reaction mixture heated to reflux for 15 min. The solvent was removed under reduced pressure, the crude oil azeotroped twice with xylene and the crude material purified with column chromatography on silica eluting with ethyl acetate/hexane (1:1) to afford 0.81 g (81%) of the title compound. 1H NMR (300 MHz, CDCl3): δ 4.03 (s, 3H), 7.44 (t, J=7.9 Hz, 1H), 7.87 (dd, J=7.9 Hz, J=1.1 Hz, 1H), 8.01 (dd, J=7.9 Hz, J=1.1 Hz, 1H). 13C NMR (75 MHz, CDCl3): δ 52.46, 115.07, 124.36, 124.82, 127.54, 142.39, 150.35, 152.24, 163.88. MS (ISP): 212.0 [M+H]+.