反应详情

In the same way as in Example 1, 250 mg (0.85 mmol) of (2R*,4R*)-4-(3-fluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)pentanal, 185 mg (1.05 mmol) of 5-amino-7-fluoro-2-methylquinazoline and 0.4 ml of titanium tetraethoxide are reacted to give (2R*,4R*)-4-(3-fluoro-2-methoxyphenyl)-1-[(7-fluoro-2-methylquinazolin-5-yl)imino]-2-(trifluoromethyl)pentan-2-ol. 430 mg of resultant crude imine are cyclized in the same way as in Example 1 at −30° C. using 8 ml (8 mmol) of 1 M boron tribromide solution to give the desired product. Column chromatography on silica gel (hexane/ethyl acetate 0-75%) yields 67 mg of product.