FOERFARANDE FOER FRAMSTAELLNING AV NAPROXEN.

摘要

Process for preparing Naproxen via a sequence of stereospecific reactions which comprises: condensation of 1-chloro-2-methoxy-naphthalene with a (S)-2-halo-propionyl halide according to the Friedel-Crafts reaction, ketalization of the thus obtained (S)-2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)-propan-1-one, rearrangement of said ketal to afford an ester, hydrolysis of the ester and removal of the chlorine atom in 5-position by hydrogenolysis. New (S) 2-halo-1-(5'-chloro-6'-methoxy-2'-naphthyl)-propan-1-ones.