Maneanese(III)-Mediated Intermolecular Cyclization Reaction Alkenes and Active Methylene Compounds

Article abstract of DOI:10.1002/jhet.5570340114

The reaction of 1,1-diphenylethene 1,1-bis(4-chlorophenyl)ethene, 1,1-bis(4-methylphenyl)ethene, and 1,1-bis(4-methoxyphenyl)ethene with 3,5-diacetyl-2,6-hepatanedione in the presence of manganese(III) acetate in acetic acid at 80° yielded 4,6-dacetyl-8,8-diaryl-1,3-dimethyl-2,9-dioxabicyclo[4.3.0]non-3-enes (41-48%), 5-acetyl-2,2-diaryl-6-methyl-dihydrobenzo[b]furans (20-21%), 3-acetyl-5,5-diaryl-2-methyl-4,5-dihydrofurans (5-10%), and benzophenones (3-7%). Similarity, the reactions of 1,1-diarylethenes with dimethyl 2,4-diacetyl-1,5-pentanedioate or diethyl 2,4-diacetyl-1,5-pentanedioate gave the corresponding 4,6-bis(alkycarbonyl)-8,8-diaryl-1,3-dimethyl-2,9-dioxabicyclo[4.3.0]non-3-enes in moderate yields.