A simple synthesis of 5-methyl-2-ethylthiazole

Abstract

5-Methyl-2-ethylthiazole II. A mixture of 1.6 g of amine I, 0.6 g of sulfur, and 25 ml of DMF was heated at 50oC for 1.5 h. Then the mixture was cooled, diluted with water, and treated with diethyl ether; the ether extracts were washed with water, dried over CaCl2, and fractionated. A fraction (1.1 g) containing, according to GLC data, 82% II (yield 61%) was obtained. H NMR spectrum, d, ppm: 1.34 t (3H, CH3CH2, J 7.5 Hz), 2.40 d (3H, CH3CS, J 1.2 Hz), 2.94 q (2H, CH2CS, J 7.5 Hz), 7.26 q (1H, HC=, J 1.2 Hz). C NMR spectrum, dC, ppm: 11.98 (CH3C=), 14.18 (CH3CH2), 26.95 (CH3CH2), 132.55 (CH3C=), 139.70 (HC=C), 171.34 (C=N). Found (from mass spectrum): M 127. C6H9NS. Calculated: M 127.