Optically active nine-membered rings incorporating the 8- and 8′-positions of 1,1′-binaphthyl

Abstract

Diethyl sodiomalonate reacts readily with 8,8′-bisbromomethyl-1,1′-binaphthyl to form a nine-membered carbocyclic ring: this behaviour is similar to the reactions of diethyl sodiomalonate with 2,2′-bisbromomethylbiphenyl to form a seven-membered ring, and with o-xylylene dibromide to form a five-membered ring. The preparation of diethyl 8,9-dihydro-7H-cyclonona[1,2,3-de:4,5,6-d′e′]dinaphthalene-8,8-dicarboxylate, in the racemic and in the optically active state, and of derived substances, is described.