Methyl iodide → 4-Thiazolecarboxylic acid, 4,5-dihydro-4-methyl-2-phenyl-

Participants

Reaction Steps

Cysteine, benzonitrile, and 5 equivalents of triethylamine were refluxed in ethanol for 6-8 hours to obtain a 66-70% yield of 2-phenylthiazoline-4-carboxylic acid. The 2-phenylthiazoline-4 carboxylic acid was reacted with 2.05 equivalents of base and 1 equivalent of methyl iodide in tetrahydrofuran at 0° C. to form 2-phenyl-4-methylthiazoline-4 carboxylic acid. The 2-phenyl-4-methylthiazoline-4 carboxylic acid can be resolved and isolated as the (S)-enantiomer using emulsion crystallization, and subsequently hydrolyzed with hydrochloric acid, thereby obtaining (S)-2-methylcysteine hydrochloride.

Provenance & Evidence