Stereoselective epoxidation of 2-arylidene-1-indanones and 2-arylidene-1-benzosuberones
作者:W. Adam、J. Hal�sz、Z. J�mbor、A. L�vai、C. Nemes、T. Patonay、G. T�th
DOI:10.1007/bf00817259
日期:——
Oxidation of the (E) and (Z) isomers of 2-arylidene-1-indanones (1) and 2-arylidene-1-benzosuberones (4) by alkaline hydrogen peroxide (method i) afforded the spiroepoxides trans-2a-g and trans-5a-g from both isomers as sole products in high yields. On the other hand, dimethyldioxirane epoxidation (method ii) of the (E) isomers 1a-g and 4a-g gave the corresponding trans spiroepoxides in good yields, whereas the (Z) isomers 1a, c, e and 4a, c, e led to the cis spiroepoxides in moderate yields. Dimethyldioxirane oxidation (method ii) of (Z)-1c and (Z)-4c, e gave diones 3c and 6c, e as by-products as well. Epoxidation of(Z)-1a, c, e and (Z)-4a, c, e by m-chloroperoxybenzoic acid (method iii) resulted in ca. 6:1 mixtures of cis-2a, c, e and trans-2a, c, e or cis-5a, c, e and trans-5a, c, e spiroepoxides.