A different route to the synthesis of 9,10-disubstituted phenanthrenes

J Org Chem. 2005 Aug 5;70(16):6508-11. doi: 10.1021/jo050646f.

Abstract

We here report the synthesis of 10-aryl-9-hydroxy- and 10-aryl-9-aminophenanthrenes by reaction of the anions of 9-phenanthrol and 9-aminophenanthrene, respectively, with aryl halides (iodobenzene, 4-iodoanisole, 9-bromophenantrene). Good yields of 9,10-disubstituted phenanthrenes were obtained in these reactions (>75% and approximately 50% for the 9-amino and 9-hydroxyphenanthrene rings, respectively). Extension of the procedure to the reaction of both anions with o-dihalobenzenes leads to the synthesis of the ring closure products (aza- or oxa-indeno[1,2-l]phenanthrene), which bear a pentacyclic aromatic condensed ring system, although in lower overall yields (approximately 35%).