Barium manganate in microwave-assisted oxidation reactions: synthesis of solvatochromic 2,4,6-triarylpyrimidines

Synthesis of 2,4,6-trisubstituted pyrimidines by tandem oxidation/heterocyclocondensation of propargylic alcohols and amidines is effected rapidly and efficiently under microwave dielectric heating using barium manganate as oxidant. Irradiation at 150 °C in ethanol-acetic acid for 45 min results in dramatic improvements in yield over the corresponding manganese dioxide-mediated method and establishes a rapid route to triarylpyrimidines in order to investigate their photophysical properties.

A series of π-extended pyrimidines with unusual photophysical properties is prepared rapidly and efficiently by microwave-assisted tandem oxidation/heterocyclocondensation using BaMnO4.