Synthesis of (±)-[4aα,4bβ,10bβ,12aβ]-9-halogeno-2-methyl-1,2,3,4,4a,4b,5,6,10b,11,12,12a-dodecahydronaphtho[2,1-ƒ]isoquinolines

Abstract

Treatment of 5-(2-arylethyl)-1,2,3,4,5,6,7,8-octahydroisoquinolines with 48% HBr resulted in isomerisation of the double bond and subsequent cyclisation at position 6 of the octahydroisoquinoline ring system to give (±)-[4aα,4bβ,10bβ,12aβ]-9-halogeno-2-methyl-1,2,3,4,4a,4b,5,6,10b,11,12,12a-dodecahydronaphtho[2,1-ƒ]isoquinolines. The products obtained represent novel analogues of aza-D-homoestranes. No reaction was observed with the corresponding 5,5-disubstituted octahydroisoquinolines. An X-ray crystallographic study of compound 10(X = Br) is described.