Process for the synthesis and recovery of tetrahydro-N-[1-methyl-1-[3-(1-methylethenyl)-phenyl]ethyl]-2-oxo-1-H-py rrolo-1-carboxamide

Abstract

The present invention discloses a process for the preparation of tetrahydro-N-[1-methyl-1-[3-(1-methylethenyl)phenyl]ethyl]-2-oxo-1-H-pyrro lo-1-carboxamide which is comprised of (1) reacting m-isopropenyl .alpha.,.alpha.-dimethylbenzylisocyanate with 2-pyrrolidinone at a temperature which is within the range of about 80.degree. C. to about 150.degree. C. to produce a molten reaction product; (2) mixing the molten reaction product with an aqueous emulsifier solution to form an aqueous medium, wherein the aqueous emulsifier solution contains from about 0.1 weight percent to about 10 weight percent emulsifier, and wherein the weight ratio of the molten reaction product to the emulsifier solution in the aqueous medium is within the range of 1:0.5 to 1:100; (3) allowing the tetrahydro-N-[1-methyl-1-[3-(1-methylethenyl)phenyl]ethyl]-2-oxo-1-H-pyrro lo-1-carboxamide in the aqueous medium to crystallize under conditions of agitation into the form of essentially spherical particles; and (4) recovering the tetrahydro-N-[1-methyl-1-[3-(1-methylethenyl)phenyl]ethyl]-2-oxo-1-H-pyrro lo-1-carboxamide particles from the aqueous medium by filtration.

Dependencies are inferred from the claim text.