Methyl isothiocyanate → N-Methyl-4-(pyrazin-2-yl)piperazine-1-carbothioamide

Participants

Reaction Steps

To a solution of 6.56 g. of 1-(2-pyrazinyl)piperazine (U.S. Pat. No. 2,606,906) in 40 ml. of anhydrous ether is added a solution of 2.92 g. of methyl isothiocyanate in 40 ml. of anhydrous ether, dropwise over a periodof 10 minutes. This suspension is stirred for one hour and the solid is collected and washed. This solid is dissolved in a mixture of 200 ml. of benzene and 50 ml. of ethanol with heat and then cooled to room temperature over 48 hours. The resulting solid is dissolved in 400 ml. of ethanol:ethyl acetate (1:3), concentrated to 200 ml. and chilled. The resulting solid is collected giving 4.34 g. of the desired product as white crystals, m.p. 197°-200° C.

Provenance & Evidence