Aza‐7‐norbornadiènes

Abstract

97. Aza-ir-norbornadi&nes [l] par R. Kitzing. R. Fuchs, M. Joyeux et €1. Prinzbach Labratoire de Chimie organique, Universit6 de Lausanne (4 I\-68) Summavy. Several 7-aza-norbornadiene-derivatives have been synthesized. Their UV.-ant1 NMR.-data are reported.Les aza-7-norbornadihnes 2 sont les premiers produits de la voie de synth2se [Z] des aza-3-quadricyclanes substituks 3 ou des azCpines correspondantes 4, selon le schCma suivant :

Influence of Lewis acids on the Diels–Alder reaction. Part I. An improved synthesis of 7-azanorbornadiene, 3-azaquadricyclane, and azepine derivatives

“…56-57" (2). Samples prepared in this laboratory by the thermal or Lewis acid-promoted reaction, although identical (p.m.r., infrared (i.r.…”

“…For one such study we chose the reaction of l a with DMAD. When this work was started the adduct 2a had not been ~r e p a r e d .~ Our approach to the synthesis of 2a differs significantly from that of Prinzbach (2). We felt that the combination of milder reaction conditions, the irreversible nature this adduct to be prepared in the presence of AlCl,.…”

“…Prinzbach and co-workers (1,2) have recently reported the preparation of a number of 7-azanorbornadiene derivatives (2a-2e). These adducts were prepared by heating the appropriate N-substituted pyrrole (la-le) with a large excess of dimethyl acetylenedicarboxylate (DMAD).…”

“…Up until 1968 the only 7-azanorbornadiene derivatives reported were those prepared from N-benzyl-, N-1-naphthyl-, and N-carbomethoxypyrrole with acetylenedicarboxylic acid (3,4,16), and recently Prinzbach and co-workers have isolated the corresponding adduct of N-methylpyrrole (2). These adducts exist as zwitterions and ;their isolation has been attributed to their insolubility in the reaction medium (4).…”

“…All spectral data are reported in the Experimental. Since Prinzbach and co-workers (2) did not analyze the p.m.r. spectrum of 2a the data for this compound have also been included.…”