An efficient and selective method for metal- and oxidant-free deaminated esterification of tertiary amines is presented. In this protocol, ynoates play a key role to activate the Csp3−N bond through a process of in situ generation of zwitterionic salts. The transformations show that Csp3−N bond in the zwitterionic species has a lower dissociation energy than Csp2−N bond, leading to break preferentially