反应详情

[5-(4-Fluoro-phenyl)-2-(2-triisopropylsilanyloxy-phenyl)-[1,3,4]thiadiazol-3-yl]-(2,4,6-trifluoro-phenyl)-methanone (3.4 mmol), prepared in a similar manner as described for [5-(4-fluoro-phenyl)-2-(3-methoxy-2-triisopropylsilanyloxy-phenyl)-[1,3,4]thiadiazol-3-yl]-(2,4,6-trifluoro-phenyl)-methanone in example 3, is treated with tetrabutylammonium fluoride (1.0 M in THF) (5.1 mmol) at room temperature for 40 minutes. Methyl bromoacetate (5.1 mmol) is then added. After 12 hours, the reaction is complete as determined by LC/MS. Purification is accomplished by silica flash chromatography (25% EtOAc/hexane) to give {2-[5-(4-fluoro-phenyl)-3-(2,4,6-trifluoro-benzoyl)-2,3-dihydro-[1,3,4]thiadiazol-2-yl]-phenoxy}-acetic acid methyl ester: 1H NMR (400 MHz, CDCl3) δ 7.61 (s, 1H), 7.54 (m, 2H), 7.04 (m, 3H), 7.01 (d, J=8.4 Hz, 1H) 6.95 (bs, 2H), 4.94 (s, 2H), 4.01 (s, 3H). MS: (ES+) 535.1 (M+1); LC/MS (ES+): 535.1 (M+1)+.

1. customPurification