6,6-Dimethyl-4,8-dioxospiro[2.5]octane-1,1,2,2-tetracarbonitrile in the synthesis of heterocyclic compounds of the 2,3-dihydrofuran and 5,6,7,8-tetrahydro-4h-chromene series

Article abstract of DOI:10.1007/BF02315175

6,6-Dimethyl-4,8-dioxospiro[2.5]octane-1,1,2,2-tetracarbonitrile (III), synthesized by the interaction of tetracyanoethylene with 2-bromo-5,5-dimethyl-1,3-cyclohexanedione, reacts with alcohols and ketoximes to form 2-alkoxy-2-(3-alkoxycarbonyl-2,2-dimethylpropyl)-5-amino-3-dicyanomethylene-4- cyano-2,3-dihydrofurans and 2-alkylidenaminoxy-2-(3-alkylidenaminoxycarbonyl-2,2-dimethylpropyl)-5-amino-3- dicyanomethylene-4-cyano-2,3-dihydrofurans. Compound III with triarylphosphines forms 2-(triarylphosphoranilidenamino)-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H- chromene-3,4,4-tricarbonitriles. 1998 Plenum Publishing Corporation.