The synthesis of N,N-dimethyl-N-[(pyrrol-l-yl)methyl]anilinium chloride (14) and of the corresponding p-toluidinium salt 15 is described. These salts, when dissolved in polar solvents, are shown to be in equilibrium with 1-(chloromethy1)pyrrole (17) and thereby potentially with the 5-azoniafulvene ion (2). Consequently, they react under very mild conditions (MeCN, 60') with enamines to give pyrrolizine derivatives in acceptable yield (40-50%). The process is rationalized in terms of an initial Mannich-type reaction which is immediately followed by a cyclization.

Reaction of the 5-Azoniafulvene Ion with Enamines: A New Approach to Pyrrolizines.-The salt (III), when dissolved in polar solvents, is in equilibrium with 1-chloromethyl-pyrrole and thereby potentially with the title ion. Consequently, (III) reacts with the enamines (IV) and (VIII) under very mild conditions to give pyrrolizidine derivatives by a new method. A reaction pathway is described. -(SCHAERER, D.; JINDRA, V.; BRINGHEN, A. O.; BURGER, U.; Helv.

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