Ready Thermal DDQ Dehydrogenation of Some Methylcyclopropanes Activated by a Spiro-Fused Fluorene Group

Article abstract of DOI:10.1246/cl.1987.863

Some methylcyclopropanes activated by a spiro-fused fluorene group were readily dehydrogenated by DDQ, but not by chloranil, to give a butadiene derivative, which reacted further with DDQ to afford 7-(o,o'-biphenylene)-3,4-dichloro-1,6-dicyano-9-alkyl-bicyclo<4.4.0>deca-3,8-diene-2,4-dione.In contrast, methylcyclopropanes substituted merely by two phenyl groups were reluctant to undergo the dehydrogenation.