Regioselectivity in reactions of alkynylmetal complexes with pyrimidinones
作者:Frode Rise、Kjell Undheim
DOI:10.1016/0022-328x(85)80160-1
日期:1985.8
Regioselectivity is observed in 11-adduct formation between phenylethynyltriisopropoxytitanium and 2(1/H)-pyrimidinones; the new carbon-carbon bond is formed at C(4). In contrast the 3,4- and 3,6-dihydro products are formed together from the corresponding magnesium and lithium reagents, but from the magnesium compound the major product is the 3,6-dihydro isomer. Ethynylmagnesium bromide gives equimolar