Prospects of fused polycyclic nitroazines as thermally insensitive energetic materials

Indolizines carrying various substituents in positions 5-8 were obtained from readily available 2-(1H-pyrrol-1-yl)nitriles and α,β-unsaturated ketones or aldehydes in a one-pot procedure. Michael addition of the deprotonated aminonitriles to the acceptors followed by acid-catalyzed electrophilic cyclization produces 5,6-dihydroindolizine-5-carbonitriles. From these stable intermediates, substituted indolizines were obtained via base-induced dehydrocyanation.

One-Pot Synthesis of Polysubstituted Indolizines by an Addition/Cycloaromatization Sequence

A variety of N-acylhydrazones were synthesized under microwave irradiation within 2.5−10 min, starting from benzo, salicyloyl, and isonicotinic hydrazides. The protocol developed employs microwave irradiation in the absence of solvents and catalysts, leading to high yields. The results are reproducible in a 500 mg to 5 g scale.

Fast Synthesis of N-Acylhydrazones Employing a Microwave Assisted Neat Protocol

Hydrazones are important and interesting class of organic nitrogen compounds exhibiting a broad spectrum of biological activity like antimicrobial [1], antiinflammatory [2], antitumor [3], etc. Among these versatile compounds isatin-based hydrazones are worthy of notice due to a number of useful properties. These derivatives are interesting as plasticizers and antioxidants [4], various enzyme inhibitors [5, 6] and complexing agents [7, 8]. Furthermore, there are data on high antimicrobial activity of some isatin-3acylhydrazones [9, 10]. However, one factor which does not allow performance of a more extensive research in this field is the low solubility of the target compounds in the water.

First examples of isatin acylhydrazones with ammonium fragment

Unsymmetrical and symmetrical azines toward application in organic photovoltaic

http://link.springer.com/content/pdf/10.1007/BF01106649.pdf

Hydrazones: Communication 49. The structural formulas of benzoylhydrazones of aromatic aldehydes

1.

The aroylhydrazones with intramolecular hydrogen bonding exist in acylhydrazone form with a high degree of electron delocalization.




2.

The preferred form in nonpolar solution is an equilibrium mixture of three conformers of the salicyloylhydrazones of several different aldehydes, these differing in the degree of rotation around the amide N-C bond and in the type of H-bonding (-OH...O=C or N-H...-OH).

Hydrazones 62. The structures of aroylhydrazones with intramolecular hydrogen bonding

1.

On the basis of the data of the method of dipole moments, potentiometric titration, and vibrational spectroscopy, a flat s-trans-configuration of the azines of certain aromatic aldehydes was proposed.




2.

The values of pKa of symmetrical and nonsymmetrical benzalazines are determined by the interaction of the proton not only with one of the nitrogen atoms, but also with the entire conjugated azine fragment.






.

Structure and certain physicochemical properties of azines

http://link.springer.com/content/pdf/10.1007/BF00922793.pdf

Hydrazones: Communication 42. Study of the structure of arylhydrazones of acyl halides by the method of dipole moments

On the basis of VU and PMR spectroscopic data with the aid of the method of experimental structures and the method of dipole moments it was concluded that the products of the reaction of 1,4-dichlorophthalazine with ammonia, methylamine, and aniline in solutions and in the crystalline form exist primarily as Z conformers of the amino tautomeric form. Conversion to the tautomeric imino form was established for 1-phenylamino-4-chlorophthalazine in a number of solvents. The imines of 2-methyl-4-chlorophthalazine exist as the E isomers.

S. A. Flegontov

Papers

Hydrazones: Communication 49. The structural formulas of benzoylhydrazones of aromatic aldehydes

Hydrazones 62. The structures of aroylhydrazones with intramolecular hydrogen bonding

Structure and certain physicochemical properties of azines

Hydrazones: Communication 42. Study of the structure of arylhydrazones of acyl halides by the method of dipole moments

Spectra and structure of 1-aminophthalazines