Efficient syntheses of some 1-naphthylalkyl ketones and studies on their autooxidation in basic medium

Article abstract of DOI:10.1016/S0040-4020(01)98894-5

Birch reductions of 4,6-dimethoxy-1-naphthylalkyl ketones 1 provided in fair to good yields the demethoxylated products, 6-methoxy-1-naphthylalkyl ketones 2(a-g), not easily accessible by other procedures. Autooxidation of these ketones in basic medium afforded the diketones 6(a-c), the acid 2h, and interestingly the phenol 5. Extension of this reduction to the related tricyclic ketone 8 afforded 9a, the phenolic ketone 9b; and significantly the dihydrocoumarin derivative 10 as a result of autooxidation of 9a. The mechanisms for demethoxylation and autooxidation have been discussed.