COUMARIN-CONTAINING AMINO-ACIDS AND OXY ACIDS AS CHIRAL DISCRIMINATING AGENTS - PART III - NOVEL CRYSTALLINE (R)-(-O-COUMARINYL AND (S)-(-)-O-COUMARINYL LACTIC ACIDS AS CHIRAL DERIVATIZING AGENTS FOR H-1-NMR INSPECTION OF OPTICAL PURITIES OF ALCOHOLS AND AMINES())

Commercially available (S)-(-)-ethyl lactate and (R)-(+)methyl lactate were quits simply coupled with commercial 4-hydroxycoumarin by the Mi tsunobu reaction followed by alkaline hydrolysis to furnish new crysta lline optically pure (R)-(+)- and (S)-(-)-O-coumarinyllactic acids[RCL OH and SCLOH] in good yields. Diastereomeric esters and amides derived easily and quantitatively from these acids were subjected to chiral s hift H-1 NRR examination revealing that these were efficient and relia ble chiral derivatizing agents. Either racemization or kinetic resolut ion was not induced during derivatization.