Preparation of N-monosubstituted carbamates
AssigneeAtlantic Richfield Company
InventorJohn J. McCoy
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Abstract
An improved process for the preparation of N-monosubstituted carbamates by reacting an aromatic primary amine, urea and a monohydric aliphatic alcohol in the presence of a strongly basic tertiary amine catalyst and optionally an inert solvent.
Claims22
A process for the preparation of an N-monosubstituted carbamic acid ester which comprises reacting an aromatic primary amine having the formula R(NH.sub.2)n wherein R is a substituted or unsubstituted aryl or aralkyl group containing one or more benzenoid rings which may be fused or joined by single valency bonds and n is an integer of 1 to 6, with urea and at least a stoichiometric amount of a monohydric aliphatic alcohol, based on the aromatic amine and, having from 1 to 10 carbon atoms at a temperature in the range of from about 100.degree. C. to 250.degree. C. in the presence of a catalytic amount of a strongly basic aliphatic, cycloaliphatic, araliphatic or aromatic tertiary amine containing from 1 to 18 carbon atoms.
A process for the preparation of ethylphenylcarbamate which comprises reacting aniline with urea and at least a stoichiometric amount of ethyl alcohol based on the aromatic primary amine, at a temperature of from about 125.degree. C. to 225.degree. C. at a molar ratio of aniline to urea in the range of from about 5:1 to 0.25:1 in the presence of from about 1 to 100 mole percent, based on the aniline employed, of a strongly basic aliphatic, cycloaliphatic, araliphatic or aromatic tertiary amine containing from 1 to 18 carbon atoms.
A process for the preparation of a urethane which comprises reacting an aromatic primary amine with urea and an alcohol at a temperature of from about 100.degree. C. to 250.degree. C. in the presence of a tertiary amine.
Dependencies are inferred from the claim text.