Resolution s. under Stereoisomers

Resolution s. under Stereoisomers Resorcinol monesters s. 1,3-Diol monoesters Resorcinols, synthesis 2, 648 labeled 2, 648 suppl. 27 Retention of... 

The 0 -phenyl-0 -piperidyl-(2)-acetic acid methylester of BP 135° to 137°C under 0.6 mm pressure is obtained in theoretical yield by hydrogenation of 50 g of 0 -phenyl-0 -pyridyl-(2)-acetic acid methylester in glacial acetic acid in the presence of 1 g of platinum catalyst at room temperature, while taking up 6 hydrogen atoms. Reaction with HCI gives the hydrochloride. Resolution of stereoisomers is described in U.S. Patent 2,957,880. 

This is a review of synthetic efforts made at these laboratories in recent years. Stereoisomers of sex pheromones of various insect species were synthesized in order to facilitate identification and permit more thorough evaluation of their potential in insect control programs. Syntheses are described for pheromones of the stable fly, tsetse fly, southern and western corn rootworms, and the Mediterranean fruit fly attractant, trimed-lure. In each instance centers of asymmetry were generated that made use of diastereomer formation using readily available (R)- and (S)-a-methyl-benzylamine. Resolutions were achieved either by preparative HPLC, or fractional crystallization of amides. The latter technique was rendered synthetically useful for the preparation of configurationally pure acids by virtue of transformations wrought upon the amides that made them subject to cleavage under very mild conditions. 

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