Intramolecular cyclization of allylic propiolates mediated by the addition of stannyl radicals: A new synthetic route to α-methylene-γ-butyrolactones
作者:Eun Lee、Sung Bo Ko、Kyung Woon Jung、Moon Ho Chang
DOI:10.1016/s0040-4039(01)80626-2
日期:1989.1
Allylic propiolates react with tributyl- or triphenylstannane to yield α-(stannyl)methylene-γ-butyrolactones. α-Methylene-γ-butyrolactones are easily prepared by destannylation.
Photoisomerisation of (E)-iodoalkylidene lactones a route to (Z)-iodoalkylidene Lactones
作者:Gerald Haaima、Lyall R. Hanton、Mary-Jeanne Lynch、Simon D. Mawson、Anne Routledge、Rex T. Weavers
DOI:10.1016/s0040-4020(01)85076-6
日期:1994.2
Photochemically induced free-radical cyclisation of iodo acetylenic esters provides low yields of mixtures from which both (E)- and (Z)- iodoalkylidene lactones may be isolated. However, photoisomerisation of (E)-iodolkylidene lactones, which have previously been obtained in good yields by dibenzoyl peroxide induced cyclisation of iodo acetylenic esters, provides (E)/(Z)-mixtures from which the previously