反应详情

A mixture of 25 g of 5,6-dihydro-2-(methylthio)-4H-1,3-oxazine (Clapp, et al., J. Heterocyclic Chemistry, 5, 107 (1968)), 25 g of methyl nitroacetate and a catalytic amount of zinc chloride was heated to 90° over one hour and maintained at that temperature for an additional hour. The mixture then was cooled and triturated with ether to effect crystallization. The solid was recrystallized from ethanol to give methyl nitro(tetrahydro-2H-1,3-oxazin-2-ylidene)acetate (1A), as a yellow solid, m.p.: 132°-3°.

1. temperaturemaintained at that temperature for an additional hour
2. temperatureThe mixture then was cooled
3. customtriturated with ether
4. customcrystallization
5. customThe solid was recrystallized from ethanol