5-Amino-1,2-dihydroquinolin-2-one → 5-{[(2R*,4R*)-4-(3,4-difluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)hexylidene]amino}quinolin-2(1H)-one

Participants

Reaction Steps

In the same way as in Example 29, 210 mg (0.64 mmol) of (2R*,4R*)-4-(3,4-difluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)hexanal, 132 mg (0.97 mmol) of 5-aminoquinolin-2(1H)-one and 0.27 ml of titanium tetraethoxide are reacted to give 5-{[(2R*,4R*)-4-(3,4-difluoro-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)hexylidene]amino}quinolin-2(1H)-one. 234 mg of crude imine are cyclized in the same way as in Example 29 at −20° C. with 2 ml (2 mmol) of 1 M boron tribromide solution to give the desired product. Preparative thin-layer chromatography on silica gel (hexane/2-propanol 17%) yields 15.4 mg of the desired product.

Provenance & Evidence