K. G. Dongol, J. Krüger, M. Schnebel
Dec 15, 1999
Citations
0
Influential Citations
6
Citations
Journal
Inorganica Chimica Acta
Abstract
Abstract The syntheses of methoxy substituted benzocyclobutenone and benzocyclobutenedione tricarbonylchromium complexes rac - 4 and rac - 10 are reported. rac - 4 is preferentially obtained by a [2+2] cycloaddition of 3-methoxy-1,2-dehydrobenzene with diethoxyethene followed by complexation and acetal hydrolysis, whereas rac - 10 is prepared by acetalization of the ligand followed by complexation and hydrolysis. rac - 4 is stereoselectively reduced to the benzocyclobutenol complex with LiAlH 4 in high yield. However, the anion driven ring opening–cycloaddition sequence furnished only poor selectivity. Vinyl Grignard addition to the 3-methoxybenzocyclobutenedione complex rac - 10 gave the 1-vinyl adduct, which was characterized by an X-ray structure analysis.