Synthesis of Condensed 4H-Pyrans: The reaction of 1,1-dimethyl-3,5-diketocyclohexane with cinnamonitriles

Cyclohexano-4H-pyrans could be prepared by reaction of 1,1-dimethyl-3,5-diketo-cyclohexane 2 with cinnamonitriles 1 and converted into 2-amino-4-aryl-1,4-dihydro-7,7-dimethyl-5-oxocyclohexanopyridin-3-carbonitrile 7a, b ; 7,7-dimethyl-2,5-dioxo-4-phenyl-1,2,3,4-tetrahydro-cyclohexanopyridin-3-carbonitrile 8 , 5-aryl-1,1-dicyano-2-phenyl-8,8-dimethyl-1,2,3,4,6,7,8,9-octahydro-3-azaacridin-4,6-dione 12a, b and 2-thioxo-4-amino-5-aryl-3-benzoyl-2,3-dihydro-9,9-dimethylcyclohexano-g]-4H-pyrano2,3-d]pyrimidin-7-one 14a, b .