Formation of norcaradiene derivatives from an α-oxocarbene and aromatic compounds: their conversion into novel acenaphtho[1,2-b]benzofurans and their silver ion catalysed aromatisations

Abstract

Photolysis of 2-diazoacenaphthen-1-one in benzene gives spiro[acenaphthene-1,7′-cis-norcara-2′,4′-diene]-2-one (3) which rapidly isomerises to 2-phenylacenaphthen-1-one under silver perchlorate catalysis and gives the novel acenaphtho[1,2-b]benzofuran (5; X = H) in the presence of dicyanodibenzoquinone (DDQ), other aromatic receptors giving similar results.