Claims for Patent: 6,528,678

Summary for Patent: 6,528,678

Title:	Phosgene-free process for preparing carbamates
Abstract:	A phosgene-free method for preparing a carbamate from a compound containing an amine group involves reacting the compound with an alkylating agent in the presence of carbon dioxide and cesium carbonate. A reaction can take place under standard pressure and temperature conditions and produces carbamates in a high yield with low by-product formation.
Inventor(s):	Lee; Byung H. (Kalamazoo, MI)
Assignee:	Pharmacia& Upjohn Company (Kalamazoo, MI)
Application Number:	10/000,756
Patent Claims:	1. A method for preparing a carbamate from a compound containing an amine group comprising reacting the compound with chloromethyl pivalate in the presence of carbon dioxide and cesium carbonate. 2. The method of claim 1, wherein said compound contains a primary amine group. 3. The method of claim 1, wherein said compound contains a secondary amine group. 4. The method of claim 1, wherein said compound is an amino acid. 5. The method of claim 1, wherein the reaction takes place in a polar aprotic solvent. 6. The method of claim 1, wherein the amino group is a piperazine group. 7. The method of claim 5, wherein the solvent is dimethyl formamide. 8. The method of claim 1, wherein the reaction takes place under standard temperature and pressure conditions.