Formation and reaction of N-acyl-and N-methanesulfonyl-1-(3,4-dimethoxy)benzyl-7-acetoxy-1,2,3,4,6,7-hexahydro-7-methoxy-6-oxoisoquinolines(o-quinol acetates)

摘要

Oxidation of N-acyl- and N-methanesulfonyl-l,2,3,4-tetrahydro-7-methoxyisoquinolin-6-ols (7) with lead tetraacetate in dichioromethane produced quantitatively title compounds (o-QAs) (8). Treatment of N-trifiuoroacetyl and N-formyl o-QAs (Sa,b) with acetic acid at 30—400C afforded N-trifluoroacetyl and N-formyl p-QAs (9a.b), while that of N-acetyl, N-ethoxycarbonyl and N-methane-sulfonyl congeners (8c—e) gave N.N-dialkylacetamide (1(k). ethyl N.N-dialkylcarbamate (lOd), and NN-dialkylmethanesulfonamide (iSe), which are formed by elimination of a benzylic proton and subsequent cleavage of a C1—C8a bond in 9c—e.