Abstract
Detailed examinations on nitrous acid deaminations of L-phenylalanine ethyl ester (Ib) and its p-nitro (Ia) and p-methoxy (Ic) derivatives in 1 N sulfuric acid, acetic acid, and trifluoroacetic acid have shown that the reactions are highly dependent both on the solvent employed and on the substituent attached to the aromatic ring. Results may be rationalized by evaluating the changes in nucleophilicities of both the solvent and the aryl group. We clearly demonstrated that aryl groups exhibit strong neighboring group participation in deamination in trifluoroacetic acid.
