. . . "The process of claim 5 wherein R is a methyl group, phenyl group, 2-methyl-phenyl group, 4-methyl-phenyl group, 2,6-dimethyl-phenyl group, 2,4,6-trimethyl-phenyl group, 4-tert-butyl-phenyl group, 2,6-dimethyl-4-tert-butyl-phenyl group, 2,6-diisopropyl-phenyl group, 2,6-diisopropyl-4-tert-butyl-phenyl group, 1-naphthyl group, 1-naphthyl group containing alkyl and aryl substituents, 2-naphthyl group" . .