Dipyrrolo[1,2-a;2':,1'-c]pyrazines. 7. Electrophilic Substitution of Dipyrrolo[1,2-a;2',1'-c]pyrazines and 5,6-Dihydrodipyrrolo[1,2-a;2',1'-c]pyrazines via Formylation of Dipyrrolo[1,2-a;2':,1'-c]pyrazines

A series of previously unreported aldehydes has been prepared by the formylation reaction of dipyrrolo[1,2-a;2':,1'-c]pyrazines and their 5,6-dihydro analogs by DMF and phosphorus oxychloride.     

Dipyrrolo[1,2-a;2',1'-c]pyrazines. 6. Electrophilic Substitution in a Series of Dipyrrolo[1,2-a;2',1'-c]pyrazine and 5,6-Dihydrodipyrrolo[1,2-a;2',1'-c]pyrazine Derivatives. Phosphorylation of Dipyrrolo[1,2-a;2',1'-c]pyrazines

We have studied the behavior of asymmetrically substituted dipyrrolo[1,2-a;2',1'-c]pyrazines and their 5,6-dihydro analogs under phosphorylation reaction conditions.     

International Congress on the Heterocyclic Chemistry “KOST-2015” dedicated to the 100-year anniversary of the birth of Professor Aleksei Nikolaevich Kost

Russian Chemical Bulletin -     

First example of the Chan—Lam—Evans N-arylation of bispidines

Russian Chemical Bulletin - The N-arylation of N-Boc-bispidine with arylboronic acids was accomplished under the copper-catalyzed Chan—Lam—Evans reaction conditions. The reaction...     

Novel Highly Energetic Pyrazoles: N‐Trinitromethyl‐Substituted Nitropyrazoles

A new family of energetic compounds, nitropyrazoles bearing a trinitromethyl moiety at the nitrogen atom of the heterocycle, was designed. The desirable high‐energy dense oxidizers 3,4‐dinitro‐ and 3,5‐dinitro‐1‐(trinitromethyl)pyrazoles were synthesized in good yields by destructive nitration of the corresponding 1‐acetonylpyrazoles. All of the prepared compounds were fully characterized by multinuclear NMR and IR spectroscopy, as well as by elemental analysis. Single‐crystal X‐ray diffraction studies show remarkably high density. Impact sensitivity tests and thermal stability measurements were also performed. All of the pyrazoles possess positive calculated heats of formation and exhibit promising energetic performance that is the range of 1,3,5‐trinitroperhydro‐1,3,5‐triazine and pentaerythritol tetranitrate. The new pyrazoles exhibit positive oxygen balance and are promising candidates for new environmentally benign energetic materials.     

Pi-conjugated N-heterocyclic compounds: correlation of computational and electrochemical data

Electrochemical reduction potentials of a broad selection of nitrogen-containing molecules suitable as bridging (dipodal and tripodal) ligands in coordination and organometallic chemistry are reported and compared with results of semiempirical calculations. Trends of electrode potentials observed experimentally agree with respective calculated data, deviations can be explained by invoking peculiarities of the involved molecular orbitals and ligand-electrode surface interactions.     

Synthesis of unsymmetrical dienones with heteroaromatic substituents

Condensation of heteroaromatic aldehydes with 2-benzylidenecyclopentanone in a basic medium afforded a number of unsymmetrical 2,5-diarylidenecyclopentanones. According to ¹H NMR data, the dienones obtained were the E, E-isomers. Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2156–2157, September, 2005.     

Synthesis of Novel Condensed Binuclear Heterocycles Based on 1,3- and 1,5-Dicarbonyl Derivatives of 2,2-Dimethyltetrahydropyran

Treatment of 1,5- and 1,3-dicarbonyl derivatives of 2,2-dimethyltetrahydropyran with a series of binucleophiles gave condensed pyranopyrazole, pyranothiopyrimidine, pyranoisoxazole, and pyranopyridine systems.