Concepedia

Abstract

In continuation of our previous study, oxidative coupling reactions of uracil with allylsilane or enol ethers were examined using diacetoxyiodobenzene. The reaction of persilylated uracil with 3,4-dihydro-2<i>H</i>-pyran in the presence of TMSOTf and PhI(OAc)<sub>2</sub> resulted in the formation of a dihydropyranyluracil derivative, although the yield was low. In an extension of the oxidative coupling reaction, a novel glycosylation reaction using glycal derivatives as substrates was also developed. The treatment of persilylated uracil and 3,4-dihydro-2<i>H</i>-pyran with (PhSe)<sub>2</sub> and PhI(OAc)<sub>2</sub> in the presence of a catalytic amount of TMSOTf gave a 2,3-<i>anti</i>-derivative of 1-(3-phenylselanyltetrahydropyran-2-yl)uracil stereoselectively and in good yield.