2-pyrazinylnitrene and 4-pyrimidylnitrene. Ring expansion to 1,3,5-triazacyclohepta-1,2,4,6-tetraene and ring opening to (2-Isocyanovinyl)carbodiimide.
@article{Addicott20022pyrazinylnitreneA4, title={2-pyrazinylnitrene and 4-pyrimidylnitrene. Ring expansion to 1,3,5-triazacyclohepta-1,2,4,6-tetraene and ring opening to (2-Isocyanovinyl)carbodiimide.}, author={Chris Addicott and Ming Wah Wong and Curt Wentrup}, journal={The Journal of organic chemistry}, year={2002}, volume={67 24}, pages={ 8538-46 } }
Tetrazolo[1,5-a]pyrazine/2-azidopyrazine 9T/9A undergo photolysis in Ar matrix at cryogenic temperatures to yield 1,3,5-triazacyclohepta-1,2,4,6-tetraene 21 as the first observable intermediate, and 1-cyanoimidazole 11 and (2-isocyanovinyl)carbodiimide 22 as the final products. The latter tautomerizes to 2-(isocyanovinyl)cyanamide 23 on warming to 40 K. The same intermediate 21 and the same final products are obtained on matrix photolysis of the isomeric tetrazolo[1,5-c]pyrimidine/4…
27 Citations
3-Pyridazinylnitrenes and 2-pyrimidinylnitrenes.
- ChemistryThe Journal of organic chemistry
- 2014
The reaction mechanisms are discussed and supported by DFT calculations on key intermediates and pathways and there is no evidence for the interconversion of 3-pyridazinylnitrenes 9 and 2-pyrimidinylnitrene 19.
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- ChemistryJournal of the American Chemical Society
- 2011
A photochemically reversible interconversion of the seven-membered ring carbodiimides 35 and 48 and the nitrile ylides 36 and 49 is established and recyclization of open-chain nitrilides is identified as an important mechanism of formation of ring contraction products (N-cyanobenzimidazoles).
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- Chemistry
- 2008
Cyano-substituted tetrazolo[1,5-a]pyridines/2-azidopyridines 8T and 15T undergo thermal ring opening to the azides 8A and 15A. Solution photolysis causes nitrogen elimination and ring expansion to…
Pteridines: Part CXIII: Protection of pteridines
- Chemistry
- 2003
Our approach to achieve a partial synthesis of methanopterin (1) started from 6-acetyl-O4-isopropyl-7-methylpterin (20) which was obtained either by condensation from…
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- Chemistry
- 2009
Photolysis of 3-azidoquinoline 6 in an Ar matrix generates 3-quinolylnitrene 7, which is characterized by its electron spin resonance (ESR), UV, and IR spectra in Ar matrices. Nitrene 7 undergoes…
4-Quinolylnitrene and 2-quinoxalinylcarbene
- Chemistry
- 2011
Matrix photolysis of 4-quinolyl azide 22 affords 4-quinolylnitrene 21, identified by electron spin resonance (ESR) and infrared (IR) spectroscopy. Minor absorptions assigned to azirene 23 (1741 cm−1)…
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Spectroscopic Characterization of Nicotinoyl and Isonicotinoyl Nitrenes and the Photointerconversion of 4-Pyridylnitrene with Diazacycloheptatetraene.
- ChemistryThe journal of physical chemistry. A
- 2019
The spectroscopic identification of the nitrene intermediates was aided by calculations at the B3LYP/6-311++G(3df,3pd) level, and the mechanism for their generation in stepwise decompositions of the azides is discussed in the light of CBS-QB3 calculations.
Flash Vacuum Pyrolysis of Azides, Triazoles, and Tetrazoles.
- ChemistryChemical reviews
- 2017
Flash vacuum pyrolysis of azides is an extremely valuable method of generating nitrenes and studying their thermal rearrangements and preparatively useful precursors of cyanocyclopentadienes, carbazoles, and aza-analogues.