Ammonia → HCID 18954420, compound

Participants

Reaction Conditions

Reaction Steps

225 g (3.0 mols) of 2-methoxyethylamine, 180 g (3.0 mols) of urea, 1,950 g (15 mols) of 2-ethylhexanol and 3 g of dibutyltin oxide are introduced into a 4 liter round-bottom flask equipped with reflux condenser, and the mixture is heated while stirring. A vigorous evolution of ammonia sets in at temperatures above 110° C. Ammonia gas is removed through the reflux condenser and absorbed in water. Over the course of 3 hours, the temperature is increased to 180° C. (reflux), the elimination of ammonia virtually ceasing. After a further 2 hours under reflux, the mixture is freed of remaining ammonia by flushing with nitrogen and subsequently subjected to fractional distillation. After a first cut comprising mainly ethylhexanol, the desired urethane distills over at 98°-100° C./0.1 mbar as a colorless liquid (yield: 617 g=89% of theory). 27 g of a brown liquid remain as the distillation residue and solidify to give a pasty product on cooling.

Provenance & Evidence