反应详情

In the same way as in Example 1, 170 mg (0.58 mmol) of (2R*,4S*)-4-(3-fluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)pentanal, 124 mg (0.70 mmol) of 5-amino-8-fluoro-2-methylquinazoline and 0.31 ml of titanium tetraethoxide are reacted to give (2R*,4S*)-4-(3-fluoro-2-methoxyphenyl)-1-[(8-fluoro-2-methylquinazolin-5-yl)imino]-2-(trifluoromethyl)pentan-2-ol. 295 mg of resultant crude imine are cyclized in the same way as in Example 1 at −20° C. using 2.6 ml (2.6 mmol) of 1 M boron tribromide solution to give the desired product. Column chromatography on silica gel (hexane/ethyl acetate 50%) yields 25 mg of product.