Haloacetylated enol ethers: <b>15</b>. Study of the regiochemistry of the cyclo‐condensation of β‐alkoxyvinyl trihalomethyl ketones with <i>N</i>‐methyl thiourea

Abstract

Abstract A study of the regiochemistry of the cyclo‐condensation reaction of ß‐alkoxyvinyl trihalomethyl ketones with an unsymmetric dinucleophile N ‐methyl thiourea to afford a series of 1‐methyl‐3‐(4,4,4‐trifluoro[chloro]‐3‐oxo‐1‐butenyl)thioureas and the corresponding N ‐methyl pyrimidinethione derivatives is reported. The absolute assignment of the position of the N ‐methyl group in the pyrimidine ring was obtained through a nmr study based on two dimensional HMBC and NOESY experiments.