反应详情

In the same way as in Example 14, 100 mg (0.3 mmol) of 4-(4-chloro-3-fluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)pentanal, 53 mg (0.3 mmol) of 5-amino-8-fluoro-2-methylquinazoline and 0.1 ml of titanium tetraethoxide are reacted to give 4-(4-chloro-3-fluoro-2-methoxyphenyl)-1-[(8-fluoro-2-methylquinazolin-5-yl)imino]-2-(trifluoromethyl)pentan-2-ol. 140 mg of crude imine are cyclized in the same way as in Example 14 at −30° C. with 2.5 ml (2.5 mmol) of 1 M boron tribromide solution to give the desired product. Column chromatography on silica gel (hexane/ethyl acetate 50%) and subsequent preparative thin-layer chromatography on amine phase (Merck) with ethyl acetate/methanol/triethylamine 25:3:1 yield 3 mg of product and 16 mg of the dihydroxy compound Ex. 18.