反应详情

In the same way as in Example 1, 135 mg (0.46 mmol) of (2R*,4S*)-4-(3-fluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)-pentanal, 100 mg (0.63 mmol) of 5-amino-2-methylquinazoline and 0.23 ml of titanium tetraethoxide are reacted to give (2R*,4S*)-4-(3-fluoro-2-methoxyphenyl)-1-[(2-methylquinazolin-5-yl)imino]-2-(trifluoromethyl)pentan-2-ol. 260 mg of resultant crude imine are cyclized in the same way as in Example 1 at −30° C. using 5 ml (5 mmol) of 1 M boron tribromide solution to give the desired product. Column chromatography on silica gel (hexane/ethyl acetate 0-75%) yields 56 mg of product.