M. Ihara et al., SYNTHESIS OF 6-MEMBERED COMPOUNDS BY ENVIRONMENTALLY FRIENDLY CYCLIZATION USING INDIRECT ELECTROLYSIS, Journal of organic chemistry, 61(2), 1996, pp. 677-684
[Ni(cyclam)](ClO4)(2)-catalyzed indirect electroreduction of olefinic
bromides produced six-membered compounds in low to high yields. The sy
nthetic intermediate 49 of Ipecac and Corynanthe alkaloids was obtaine
d in 88% yield in a highly stereoselective manner. Lactam 66, the synt
hetic precursor of tacamonine, was prepared in 49% yield as a mixture
of two diastereoisomers. The electrolysis of the bromoacetates gave th
e debrominated compounds in good yields.