A probable mechanism for the unexpected formation of N-acetylphenylalanine in the hydrogenolysis reaction is shown in Scheme I. The key to this mechanism is the formation of the oxazolidine 2-a generally accepted common intermediate for the 0 s N acyl migration in the acylated amino alcohol system. 8 The reduction of this cyclic intermediate 2 leads to the observed acyl shift hydrogenolysis product le. 9 The two minor components, ...