N-azinylpyridinium N-aminides: tandem reactions with alpha-halocarbonyl derivatives and analogs

Pyridinium-N-(2´-pyridyl)aminide was reacted with different α-halocarbonyl derivatives and related compounds. The method allows an easy preparation of several heterocyclic building blocks, all including the 2-aminopyridine moietyAuthor wish to thank C.I.C.Y.T. for financial support (Project PM97-0074) and the Universidad de Alcalá for a grant to one of us (R.R.)

The first example of an intramolecular westphal reaction. Synthesis of a new aza-quinolizinium type system

The first example of an intramolecular Westphal condensation is described. To test the utility of this reaction, new benz(f)azino[2,1-a]phthalazinium salts have been prepared from appropriate dicarbonyl precursors.The authors wish to thank the Comisión Interministerial de Ciencia y Tecnología (C.I.C.Y.T.) (Project SAF98-0093) for financial support and one studentship (V. M. B.

Pyridinium N-(2'-azinyl)aminides: Regioselective synthesis of 2-alkylaminoazines

The regioselective alkylation of pyridinium-N-(2'-azinil)aminides with alkyl halides under mild conditions is described. The alkylation, combined with a reduction of the N-N bond, allows an easy preparation of 2-alkylaminoazines.The authors wish to thank the Comision Interministerial de Ciencia y Tecnologı́a (C.I.C.Y.T.) (Project PM97-0074) and the Vicerrectorado de Investigación, Universidad de Alcalá for financial support (Project E014/97)

N-azinylpyridinium N-aminides: an approach to pyrazolopyridines via an intramolecular radical pathway

Intramolecular radical arylation, under thermal conditions, to a pi-deficient pyridinium, linked to a pi-excessive 2-azi-nyliminopyridine moiety is described. The method allows a new entry to pyrazolo[1,5-a]pyridine nucleus