An iminium salt was easily prepared using the oxidation of amino ketene silyl acetal with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, and the subsequent nucleophilic addition to this iminium species proceeded efficiently to afford alpha-amino esters in good yields.

Ene reaction of various olefins proceeded with the iminium salt generated by the oxidation of aminoketene silyl acetal to give addition products in good yields.

Aminocarboxylic acids (hydrazinocarboxylic acids) and esters P 0270 A New Synthetic Method for α-Alkoxycarbonyl Iminium Salt and Its Reaction with Nucleophiles. -(SHIMIZU*, M.; ITOU, H.; MIURA, M.; J. Am. Chem. Soc. 127 (2005) 10, 3296-3297; Dep. Chem. Mater., Fac. Eng., Mie Univ., Tsu, Mie 514, Japan; Eng.) -Nuesgen 31-072

C-C bond formation O 0282Ene Reaction Using the Iminium Salt Generated by the Oxidation of Aminoketene Silyl Acetal. -A variety of α-amino esters (III) and (V) is produced in good yields by an imino ene reaction of the iminium salt generated by the oxidation of silyl acetal (II). -(SHIMIZU*, M.; ITOU, H.; IWAO, T.; UMEDA, Y.; Chem. Lett. 38 (2009) 7, 732-733; Dep. Chem. Mater., Fac. Eng., Mie Univ., Tsu, Mie 514, Japan; Eng.) -M. Paetzel 48-054