Trifluoromethanesulfonic anhydride → N-[2-{1-[(2 chlorophenyl)methyl]-2-n-butyl-1H-imidazol-5-yl}ethyl]phenylalanine methyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of trifluoromethanesulfonic anhydride (0.954 g, 3.38 mmol) in methylene chloride (5 ml) was cooled to -78° C. under nitrogen, and a solution of 2-n-butyl-1-(2-chlorophenyl)methyl-5-(2-hydroxyethyl)-1H-imidazole (0.9 g, 3.07 mmol), diisopropylethylamine (0.44 g. 3.38 mmol) and methylene chloride (10 ml) was added dropwise. The mixture was stirred at -78° C. for an additional 15 minutes, then a solution of the free base of phenylalanine methyl ester (prepared from 1.33 q (6.15 mmol) of the hydrochloride salt) in methylene chloride (10 ml) was added. This mixture was stirred for 2 hours at -78° C. and an additional 18 hours at ambient temperature. The reaction mixture was washed with water, dried and concentrated and the crude product was flash chromatographed with 5% methanol in ethyl acetate to yield 0.9 g (65%) of N-[2-{1-[(2 chlorophenyl)methyl]-2-n-butyl-1H-imidazol-5-yl}ethyl ]phenylalanine methyl ester.

Herkunft & Nachweise