Felbinac → 2-biphenyl-4-yl-N-[2-(3,4-bis-benzyloxy-phenyl)-ethyl]-acetamide

Participants

Reaction Steps

The intermediate 2-biphenyl-4-yl-N-[2-(3,4-bis-benzyloxy-phenyl)-ethyl]-acetamide (1) was prepared as follows: To a stirred solution of 2.85 g (7.7 mmol) of 3,4-dibenzyloxyphenethyl amine and 1.49 g (7 mmol) of 4-biphenylacetic acid in 20 ml of anhydrous dimethylformamide at 0° C., 2.5 ml (17.7 mmoles) of triethyl amine was added dropwise and then 1-4 ml (7.7 mmol) of diethyl cyanophosphonate (90% purity) was added dropwise. The reaction mixture was stirred for 22 hours and allowed to reach room temperature, and then it was poured into 300 ml of water. The precipitated solid was separated on a glass filter funnel, washed with water (3×70 ml), and air-dried overnight. This solid was recrystallized using hexanes/ethanol mixture to provide 3.1 g (84%) of grayish crystals, mp 142-144° C.

Provenance & Evidence