Solvent-free reaction of some 1,2-diaza-1,3-butadienes with phosphites: environmentally friendly access to new diazaphospholes and E-hydrazonophosphonates

[structures: see text] The present article describes the reaction between 1,2-diaza-1,3-butadienes and trialkyl phosphites, under an atmosphere of nitrogen and under solvent-free conditions, to give alkyl 3,3-dialkoxy-2H-1,2,3lambda5-diazaphosphole-4-carboxylates that, in turn, are converted into corresponding E-hydrazonophosphonates by treatment with THF:water (95:5). These latter compounds are obtained directly by the reaction of 1,2-diaza-1,3-butadienes with trialkyl phosphites in the presence of air. These compounds are useful for the further preparation of dialkyl (5-methyl-3-oxo-2,3-dihydro-1H-4-pyrazolyl)phosphonates and 2-dialkoxyphosphoryl-1,2,3-thiadiazoles.     

Effect of Metal Ions in Organic Synthesis. Part XXX. Synthesis of New 3-Carbonyl- and 3-Carboxy-1-Alkoxycarbonylaminopyrroles from Reaction Catalyzed by Copper(II) Chloride of Alkoxycarbonylazoalkenes with β-Diketones and β-Ketoesters

In the course of our previous investigations, we dealt with the direct synthesis of unknown 1-aminopyrroie derivatives, obtained by reaction of some azoalkenes with B-diketones, 8- ketoesters, or B-ketoamides under copper (II) ionscatalysis. 1-9     

Reactions of 1,2-diaza-1,3-dienes with thiol derivatives: a versatile construction of nitrogen/sulfur containing heterocycles

The synthesis of substituted 2,3-dihydro-1,4-thiazines, fused cycloalkyl-1,4-thiazines, 1,4-benzothiazines and fused cycloalkyl-1,4-benzothiazines by 1,4-addition of 1,2-aminothiols to 1,2-diaza-1,3-dienes bearing carboxylate, carboxamide, or phosphorylated groups and subsequent internal heterocyclization is described. The reaction of carboxylated 1,2-diaza-1,3-butadienes with 2-(butylamino)ethanethiol affords 1,4-thiazinan-3-ones. The solid-phase reaction of polymer-bound 1,2-diaza-1,3-butadienes with 1,2-aminothiols produces 2,3-dihydro-1,4-thiazines and 1,4-benzothiazines.