Some dichlorophenanthrenes and related compounds

Abstract

A successful attempt was made in this work to prepare two new dichlorophenanthrenes. Dimethyl 4,4'-dichloro 2,2'-diphenate was prepared in three stages from methyl anthranilate. The 4,4'-dichloro-2,2'-bishydroxymethylbiphenyl and 4,4'-dichloro-2,2'-bisbromomethyl-biphenyl compounds were prepared. The diol was converted into the 2',3" dichloro-2,7-dihydro-3,4:5,6-dibenzazeminium and the bisbromomethyl compound used to prepare the 2',3"-dichloro-2,7-dihydro-1,1-dimethyl -3,4:5,6 dibenzazepinium bromide which was subjected to Hofmann degradation conditions and the products investigated. The neutral fraction gave a small yield of 2,7-dichlorophenanthrene and the basic part gave 2,7-dichloro-9-dimethylamino-9,10-dihydrophenanthrene. For the preparation of 3,6-dichlorophenanthrene, the starting material, 4-chloroanthranilic acid, was prepared by two different routes. The acid was converted into its methyl ester and the same procedure was followed as in the preparation of 2,7-dichlorophenan-threne.Hofmann degradation was carried out under different conditions. The ultraviolet spectra of the bridged biphenyls and the infrared spectra of all new compounds are recorded and discussed. The N. M. R. spectra of 2,3"- 3',2"-dichloro-2,7-dihydro-3,4:5,6-dipenzoxepin; 4,4' - and 5,5'dichloro-2,2,-bishydroxymethyl-biphenyl and. 2,7- and 3,6-dichlorophenanthrene were studied.