Process for preparing N-monosubstituted carbamates

Claim 2

A PROCESS FOR MAKING AN N-MONOSUBSTITUTED CARBAMATE WHICH COMPRISES INTRODUCING GASEOUS HYDROGEN CHLORIDE INTO A SUBSTANTIALLY ANHYDROUS GASEOUS MIXTURE AT ABOUT 100* TO 200:C. CONTAINING A TRISUBSTITUTED UREA HAVING THE FORMULA R(NHCONR''R")N AND AN ALCOHOL, PHENOL OR NAPHTHOL HAVING THE FORMULA R""OH WHEREIN R IS ALKYL HAVING UP TO SIX CARBON ATOMS, CYCLOHEXYL, PYRIDYL, UNSUBSTITUTED PHENYL, 1,4 BUTLENE, PHENYLENE, METHYLENE DIPHENYLENE OR HALOGEN, ALKOXY, ALKYL OR NITROSUBSTITUTED PHENYL, PHENYLENE OR METHYLENE DIPHENYLENE, R'' AND R" ARE LOWER ALKYL AND R"" IS LOWER ALKYL, 4-CHLOROBUT-2-YNYL, PHENYL, CYCLOHEXYL OR NAPHTHYL AND N IS 1 TO 2.

Claim 3

A process according to claim 1 wherein the hydrogen chloride is used in excess.

Claim 4

A process according to claim 1 wherein the hydroxy compound is used in excess.

Claim 5

A process according to claim 1 wherein the reaction is carried out in an inert solvent.

Claim 6

A process according to claim 1 wherein, after completion of the reaction, the reaction mixture is flushed with an inert gas to remove residual hydrogen chloride.

Claim 7

The process of claim 1 wherein the N-monosubstituted carbamate is isopropyl N-phenyl carbamate, sec-butyl-N-phenyl carbamate, n-butyl N-phenyl carbamate, phenyl N-phenyl carbamate, isopropyl N-3-chlorophenyl carbamate, isopropyl N-3-chlorophenyl carbamate, isopropyl N-3,4-dichlorophenyl carbamate, isopropyl N-5-chloro-2-methoxyphenyl carbamate, isopropyl N-3-methylphenyl carbamate, 4-chlorobut-2-ynyl N-m-chlorophenyl carbamate, cyclohexyl N-4-nitrophenyl carbamate, cyclohexyl N-cyclohexyl carbamate, phenyl N-hexyl carbamate, 1-naphthyl N-methyl carbamate, ethyl N-benzyl carbamate, 1,4-butylene-bis-(N-phenyl carbamate), cyclohexyl N-2-pyridyl carbamate, N,N''-methylene-di-p-phenylene-bis-(isopropyl carbamate), N,N''-(2,4-tolylene)-bis-(n-butyl carbamate) or N,N''-p-phenylene-bis-(4-hydroxybutyl carbamate).

Claim 8

The process of claim 1 wherein the trisubstituted urea has the formula R(NHCONR''R'''')N and the alcohol, phenol or naphthol has the formula R''''''OH wherein R is unsubstituted phenyl, phenylene or methylene-diphenylene or halogen, alkoxy, alkyl or nitro-substituted phenyl, phenylene or methylenediphenylene, R'' and R'''' are lower alkyl and R'''''' is 4-chlorobut-2-ynyl, lower alkyl or cyclohexyl and n is 1 or 2.

Claim 9

The process of claim 1 wherein the trisubstituted urea has the formula C6H5NHCONR''R'''' and R'''''' in the compound having the formula R''''''OH is lower alkyl or cyclohexyl.

Claim 10

The process of claim 7 wherein R'''''' is isopropyl, butyl, 4-chlorobut-2-ynyl, cyclohexyl or ethyl.

Claim 11

The process of claim 7 wherein R'''''' is a linear or branched alkyl group having up to four carbon atoms.

Claim 12

The process of claim 1 wherein the pressure is atmospheric or above atmospheric.