Asymmetric Diels-Alder reaction of 1,3-butadienes with (−)-dimenthyl fumarate in the presence of BBr3 and BBr3·OEt2
作者:E. G. Mamedov
DOI:10.1134/s1070428007020054
日期:2007.2
Asymmetric synthesis of substituted cyclohexenes was performed by [4+2]-cycloaddition of (-)-dimenthyl fumarate to 1,3-butadienes in the presence of BBr3 and BBr3 center dot OEt2. The latter are efficient catalysts for this reaction. The effect of various factors on the chemical and optical yield of compounds synthesized was studied. The lowering of the reaction temperature to -70 degrees C favors increase in the enantiomeric purity of products C up to 81%. The overall yield of adducts grows with temperature and catalyst amount. The solvent character insignificantly affects the overall and optical yield of compounds obtained.