Process for preparing 2-isocyanatoalkyl esters of organic carboxylic acids
AssigneeThe Dow Chemical Company
InventorKenneth A. Burdett
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Abstract
2-Isocyanatoalkyl esters of organic carboxylic acids are prepared by reacting (a) an aqueous solution of a 2-oxazoline with (b) an organic solution of phosgene dissolved in a water-immiscible organic solvent in the presence of (c) a hydrochloric acid acceptor. As an example, 2-isocyanatoethyl methacrylate was prepared by concurrently blending an aqueous stream of 2-isopropenyl-2-oxazoline, a methylene chloride stream of phosgene and an aqueous stream of sodium hydroxide at a temperature of from about 0.degree. C. to about 10.degree. C. The reaction rate is very high and the reaction is essentially complete upon blending the reactants.
Claims4
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting
- (a) an aqueous solution of a 2-oxazoline, and
- (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of
- (c) a hydrochloric acid acceptor,
- wherein (a), (b), and (c) are added essentially simultaneously to a reaction vessel with efficient blending in essentially stoichometric amounts.
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting
- (a) an aqueous solution of a 2-oxazoline, and
- (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of
- (c) a hydrochloric acid acceptor,
- wherein said process is conducted by simultaneously introducing a precooled aqueous solution of said 2-oxazoline, a precooled organic solution of phosgene, and a precooled aqueous solution of the hydrochloric acid acceptor into a reaction vessel with vigorous stirring and cooling;
- water being present in said reaction mixture in an amount sufficient to satisfy stoichiometry of the reaction and to provide a liquid aqueous phase in the reaction mixture and said reaction temperature being maintained between about -30.degree. C. and about 25.degree. C.
Dependencies are inferred from the claim text.