1-methyl-1,3-diazinane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 168 g of hexamethylenediisocyanate in 150 ml of ethyl acetate are slowly added to a mixture of 224 g of N-methylhexahydropyrimidine and 150 ml of ethyl acetate cooled to temperatures of from 15° to 20° C. Stirring is continued at room temperature after all the diisocyanate has been added until the isocyanate band in the IR spectrum has disappeared (after about 2 hours). The solvent is removed on a thin layer evaporator at 110° C. under a vacuum produced by a water jet pump. The viscous product preferentially consists of the following bis-hexahydropyrimidine derivative: ##STR18## cooled to temperatures of from 15° to 20° C is continued at room temperature (after about 2 hours) The solvent is removed on a thin layer evaporator at 110° C. under a vacuum produced by a water jet pump