Synthesis of α,β-unsaturated spirolactams by intramolecular cyclization of endocyclic N-Acyliminium ions.
作者:Maria J. Martín、Francisco Bermejo
DOI:10.1016/0040-4039(95)01568-3
日期:1995.10
The synthesis of (±)-6-benzyl-3-methyl-3-en-1,6-diazaspiro[4.5]decane-2,7-dione (18), the spiro moiety of (±)-pandamarine has been achieved by oxidative cyclization of the (Z) and (E) isomers of 5-(N-benzyl-4-carboxamido-butylidene)-3-methyl-3-en-pvrrolin-2-one (15a) and (15b). The stereoselectivity exhibited in the intramolecular cyclization by both butylidene precursors has also been discussed.
(±)-6-苄基-3-甲基-3-en-1,6-二氮杂螺[4.5]癸烷-2,7-二酮(18)((±)-pandamarine的螺部分)的合成已实现(15a)和(15b)的5-(N-苄基-4-羧酰胺基丁烯基)-3-甲基-3-en-pvrrolin-2-one的(Z)和(E)异构体的氧化环化。还讨论了两种丁烯前体在分子内环化中显示的立体选择性。