PREPARATION OF 5-(PYRROLYLCARBONYL)-PYRIMIDINES AND 5-(IMIDAZOLYLCARBONYL)-PYRIMIDINES

2-Methylthio-5-(pyrrolylcarbonyl)-pyrimidines have been prepared from 1-methyl-2-tributylstannylpyrrole and 2-methylthiopyrimidine-5-carbonyl chloride by Pd-catalysis. Triphenylarsine was superior to triphenylphosphine as a ligand in the reaction. The reaction with phosphine ligands proceeded well when the polarization of the reactants was reversed as in the reaction between pyrrolecarbonyl chlorides and 2-methylthio-5-tributylstannylpyrimidine. 1-Methyl-5-tributylstannylimidazole has been prepared in a one-pot reaction from 1-methylimidazole in 91 % yield.