3,4,5,6,7,8-Hexahydronaphthalen-1(2H)-ones. Synthesis and photoaddition to (Z)-1,2-Dichloroethylene

Abstract

Several cyclohexanones have been converted, via cyclohexylidenebutyric acids, into 3,4,5,6,7,8-hexa-hydronaphthalen-1(2H)-ones in good yield. Cyclododecanone gives bicyclo[10,4,0]hexadec-1(12)-en-13-one. Heating 3,4,5,6,7,8-hexahydronaphthalen-1(2H)-one with polyphosphoric acid gives 1,2,3,4-tetrahydronaphthalene, but the 7-methyl octalone gives the 2- and 6-methyl tetralins. Photoreaction of (Z)-1,2- dichloroethylene with 3,4,5,6,7,8-hexahydronaphthalen-1(2H)-one gives 11,12-dichlorotricyclo[4,4,2,0]dodecan-2-one. The ethylene acetal of this adduct can be dechlorinated to give the acetal of tricyclo[4,4,2,0]dec-11-en-2-one.