Preparation and Diels‐Alder Reaction of a Reactive, Electron‐Deficient Heterocyclic Azadiene: Dimethyl 1,2,4,5‐Tetrazine‐3,6‐Dicarboxylate. 1,2‐Diazine (Dimethyl 4‐Phenyl‐1,2‐Diazine‐3,6‐Dicarboxylate) and Pyrrole (Dimethyl 3‐Phenylpyrrole‐2,5‐Dicarboxylate) Introduction

Abstract

Preparation and Diels-Alder reaction of a reactive, electron-deficient heterocyclic azadiene: dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate. 1,2-diazine (dimethyl 4-phenyl-1,2-diazine-3,6-dicarboxylate) and pyrrole (dimethyl 3-phenylpyrrole-2,5-dicarboxylate) introduction intermediate: Disodium dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate intermediate: Dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic acid intermediate: Dimethyl dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate product: Dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate product: Dimethyl 4-phenyl-1,2-diazine-3,6-dicarboxylate product: Dimethyl 3-phenylpyrrole-2,5-dicarboxylate byproduct: methyl 3-phenyl-5-carboxamidopyrrole-2-carboxylate Keywords: annulation, heterocyclic-[5]; annulation, heterocyclic-[6]; annulation, heterocyclic-[6]; cyclization, cycloaddition; Diels-Alder reactions; esterification, of dicarboxylic acids; oxidation, miscellaneous; reduction, miscellaneous; ring contraction reactions; methanol; nitrous gases, generation; zinc dust, activation; diazo compounds; dioxane, cancer suspect agent; nitrous gases, toxic; nitrous gases, toxic