Synthesis of 6-(2-furyl) and 6-(2-thienyl)-4-trifluoromethylpyrimidinones and pyrimidines from 4-(2-heteroaryl)-4-methoxy-1,1,1-trifluoro-3-buten-2-ones

The synthesis of biheterocyclic systems 6-(2-furyl)-pyrimidines and 6-(2-thienyl)pyrimidines in reasonable yields (50-67%), two 6-(2-heteroaryl)-4-trifluoromethyl-2-(1H)pyrimidinones (2a,b) and a series of ten 6-(2-heteroaryl)-4-trifluoromethylpyrimidines (3a,b 7a,b) from the cyclocondensation of 1,1,1-trifluoro-4-(2-heteroaryl)-4-methoxy-3-buten-2-ones with urea and amidines is reported. Structures of all compounds have been elucidated by elemental analysis, mass spectrometry and ¹H, 13C NMR measurements. The ¹H and 13C NMR data are systematically reported. The X-ray diffraction data for monocrystal from 2-amino-4trifluoromethyl-6-(thien-2-yl)-pyrimidine (5b) are reported.