STUDIES ON THE CHEMICAL TRANSFORMATION OF ROTENOIDS. II. REACTIONS OF ROTENONE AND ROTENONONE WITH PRIMARY AMINES
The ring transformations of rotenone and rotenonone by primary amines were investigated.The improved synthetic methods for rotenonone were also developed.Rotenone (1) underwent cleavage of C-12a and O-13 linkage to give alkylamines (2a-b), while rotenonone (5) gave 2-alkylcarbamoyl-4-alkylimino-8-methylethenyl-3-(2-hydroxy-4,5-dimethoxy)phenyl-8,9-dihydro-4H-furobenzopyrans (7a-d) as a result of nucleophilic attack on C-12 carbon.Compound 1 was oxidized bynitrosyl chloride or dimethyl sulfoxide in the presence of iodine and sulfuric acid to provide rotenonone (5) in improved yields respectively.