The Sciff base derived from glycine ethyl ester and p-chlorobenzaldehyde can be alkylated by the ion-pair extraction method as well as under catalytic liquid-liquid or solid-liquid phase-transfer conditions. This imine is compared with the corresponding benzophenone Schiff base.
Ghosez, L., Antoine, J.-P., Deffense, E., Navarro, M., Libert, V., O’donnell, M. J., Bruder, W. A., Willey, K., & Wojciechowski, K. (1982). Synthesis of Amino-acids - Alkylation of Aldimine and Ketimine Derivatives of Glycine Ethyl-ester Under Various Phase-transfer Conditions. Tetrahedron Letters, 23(41), 4255-4258. https://doi.org/10.1016/S0040-4039(00)88718-3 (Original work published 1982)