Reactivity of mannich bases. Part XIV. Synthesis of phenylbenzoquinoline and styrylbenzoquinoline derivatives and their photoreactivity

Abstract

The cyclodehydration of the 1-phenyl- and 1-styryl-3-(naphthylamino)propan-1-ones (II), (V), and (VIII) in the presence of tin(IV) chloride pentahydrate yielded the 4-phenyl- or 4-styryl-benzoquinolines or the N-methyl-benzoquinolinium salts (III), (VI), and (IX), together with the corresponding 1,2,3,4-tetrahydro-derivatives (IV), (VII), and (X).

The photoreactivity of the benzoquinoline derivatives was examined; the 4-phenylbenzoquinolines gave the phenanthro[9,10,1-def]quinolines (XI) and (XII) as a result of cyclodehydrogenation. The trans-4-styrylbenzoquinolines gave the corresponding cis-derivatives (XIII) and (XVI), the di(benzoquinolyl)diphenylcyclobutane (XV), and the polynuclear aza-derivatives with four or five condensed rings (XIV), (XVII), and (XVIII) as a result of isomerizations, dimerization, and cyclodehydrogenations, respectively.

The structures of the new compounds were assigned on the basis of their u.v. and n.m.r. spectra.