5-aminoisoquinolin-1(2H)-one → (Rac.) 5-{[4-(4-chloro-3-fluoro-2-methoxyphenyl)-2-hydroxy-4-methyl-2-(trifluoromethyl)pentylidene]amino}isoquinolin-1(2h)-one

Participants

Reaction Steps

560 mg of the mixture that consists of (rac.) 4-(4-chloro-3-fluoro-2-methoxyphenyl)-2-hydroxy-4-methyl-2-(trifluoromethyl)pentanal and (rac.) 4-(4-chloro-3-fluoro-2-methoxyphenyl)-4-methyl-2-(trifluoromethyl)-2-hydroxy-pentanoic acid ethyl ester (since aldehyde constitutes two-thirds of the mixture, 560.2 mg of the mixture corresponds to 336.1 mg (0.981 mmol) of aldehyde) is heated for two hours to 120° C. with 157.1 mg (0.981 mmol) of 5-amino-isoquinolin-1(2H)-one and 0.557 mg (1.962 mmol) of titanium tetraisopropylate in 6 ml of o-xylene. After cooling, the batch is diluted with ethyl acetate and mixed with brine. The organic phase is separated and worked up as usual. After chromatography on a Flashmaster, 144.7 mg (30.4%) of the desired compound is obtained (relative to the proportion of aldehyde in the mixture).

Provenance & Evidence