130190-00-0Relevant articles and documents
Photoisomerisation of (E)-Iodoalkylidene Lactones. A Route to (Z)-Iodoalkylidene Lactones
Haaima, Gerald,Hanton, Lyall R.,Lynch, Mary-Jeanne,Mawson, Simon D.,Routledge, Anne,Weavers, Rex T.
, p. 2161 - 2174 (2007/10/02)
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)-iodoalkylidene 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 inaccessible (Z)-isomers may be isolated by chromatography.Also reported is a collection of IR, UV and NMR spectral data, all of which provide useful information relating to the stereochemistry of the iodoalkylidene lactones.A comparison of the cryctal structures of the (E)- and (Z)-isomers of a trimehylsilyl iodomethylene lactone is also included.
