[CH3:1][C:2]1[S:6][CH:5]=[N:4][CH:3]=1.[Li]CCCC.[CH2:12]([O:19][C:20]1[CH:21]=[CH:22][C:23]([O:30][CH3:31])=[C:24]([CH:29]=1)[C:25](OC)=[O:26])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1.Cl>C1COCC1.O>[CH2:12]([O:19][C:20]1[CH:21]=[CH:22][C:23]([O:30][CH3:31])=[C:24]([C:25]([C:5]2[S:6][C:2]([CH3:1])=[CH:3][N:4]=2)=[O:26])[CH:29]=1)[C:13]1[CH:14]=[CH:15][CH:16]=[CH:17][CH:18]=1To a stirring mixture of 5-methylthiazole (3.80 g, 38.2 mmol) in dry THF (200 mL) was added n-BuLi (2.5 M in hexane, 15.3 mL, 38.2 mmol) drop wise over 20 minutes at −78° C. under nitrogen atmosphere. The mixture was stirred between −78° C. and −60° C. for 1.5 h and then cooled to −78° C. A solution of methyl 5-(benzyloxy)-2-methoxybenzoate (10.4 g, 38.2 mmol) in THF (50 mL) was added drop wise over 30 minutes. The resulting mixture was stirred at −78° C. for 30 minutes and warmed to room temperature with stirring overnight. The mixture was cooled to 0° C. and treated with water (50 mL). The resulting mixture was adjusted to pH around 6 with HCl (1N). The organic layer was dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography eluting with petroleum ether/EtOAc (3:1) to afford (5-(benzyloxy)-2-methoxyphenyl)(5-methylthiazol-2-yl)methanone (2.5 g, 19%) as a yellow gel. 3.0 g of starting material methyl 5-(benzyloxy)-2-methoxybenzoate was recovered.
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