Methanethiol → Ethyl nitro(1,3-thiazinan-2-ylidene)acetate

Participants

Reaction Steps

To a mixture of 235 g of 5,6-dihydro-2-(methylthio)-4H-1,3-thiazine and 2 g of zinc chloride at approximately 115° in a nitrogen atmosphere, 263 g of ethyl nitroacetate was added dropwise over a 1.5 hour period. The mixture was held at 110°-120° and the nitrogen atmosphere was maintained during the addition. Evolution of methyl mercaptan ceased after 45 minutes of stirring of the heated mixture when 1 g of zinc chloride was added to the stirred mixture at ca. 115°. After 1.25 hours an additional 1 g of zinc chloride was added and stirring of the mixture at ca. 115° was continued for 1.5 hours. The mixture then was poured into a cooled solution of 2/1 ether/isopropyl alcohol mixture. The crystallized product was collected, washed with ether and dried under reduced pressure to leave a tan solid which on recrystallization from methanol gave 2a as a pale yellow solid, m.p.: 105°-106°.

Provenance & Evidence