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An extensive study on the generation and reactivity of azafulvenium methides is presented, together with details of a study of the thermolysis of N-vinyl- and C-vinylpyrroles. The synthesis and X-ray structure of a new 6-oxocyclopenta[b]pyrrole derivative is also reported.

Research has been conducted on the bicyclic munchnones. The results of the intramolecular cycloaddition of these munchnones derived from 2-substituted-N-acylthiazolidine-4-carboxylic acids' cyclodehydration are presented.

Research has been conducted on the nucleophilic substitution reactions of 2-halo-2H-azirines with potassium phthalimide and aniline. Results indicate that these reactions have produced substituted 2H-azirines.

A novel route to cross-conjugated bis(enamines) is discussed as is an unusual reaction with DDQ. The procedure is that used previously for thiazolidines from cysteine methyl ester to react with aldehyes with silver carbonate and DBU. The reactions gave transient 1-substituted methyl 2-azadiene-3-carboxylates that act as Diels-Alder dienes. When it is applied to other thiazolidines, products are isolable cross-conjugated bis(enamines).

The chemistry of diazafulvenium methides generated by the thermal xtrusion of sulfur dioxide from 2,2-dioxo-1H, 3H-pyrazolo[1,5-c] [1,3]thiazoles is described. The diazafulvenium methides unsubstituted at C-7 participate in [8pie + 2pie] cycloadditions giving pyrazolo-annulated heterocycles resulting from the addition across the 1,7-position.

Nucleophilic substitution reactions of 2-halo-2H-azirines 1a, 1b, 1d, and 1e with potassium phthalimide and aniline allowed the preparation of new substituted 2H-azirines 2-5. The reactions of 2-bromo-2H-azirine 1a with methylamine led to the synthesis of alpha-diimines 7 and 8. 2-Halo-2H-azirines were also established as building blocks for the synthesis of a range of heterocyclic compounds, namely, quinoxalines 10a-10d, 3-oxazoline 14, and 2H-[1,4]oxazines 18 and 20. X-ray crystal structures of alpha-diimine 7, 3-oxazoline 14, and 2H-[1,4]oxazine 18 are reported.