Generation of quintet dinitrenes by low-temperature radiolysis of crystalline 2,4,6-triazido-3,5-dicyanopyridine

Synthesis and structure of asymmetric 2,4,6-triazidopyridines

“…However due to the complexity of growing monocrystals of aromatic polyazides and their high sensitivity to the action of X-irradiation, up to the present time data are known only for six aromatic triazides, viz. 2,4,6-triazido-sym-triazine, 2,5,8-triazido-sym-heptazine, 2,4,6-triazidopyrimidine, 2,4,6-triazido-3,5-dichloropyridine, 2,4,6-triazido-3,5-dicyanopyridine, and 2,4,6-triazido-5-chloro-3-trifluoromethylpyridine [20][21][22][23][24][25]. The synthesis and spectral characteristics of the last triazide have not been described.…”

“…The fullest information on the molecular and crytstalline structure of aromatic polyazides was obtained from data of X-ray structural investigations [20][21][22][23][24][25][26]. In particular, these data allowed the reliable prediction of the emergence of interesting magnetic properties of crystalline polyazides after their UV irradiation [26].…”

Photochemical generation of triplet—triplet nitrene pairs in aromatic diazide crystals

“…The bond lengths and bond angles in the azido groups of compounds 1 and 5 do not virtually differ from analo gous parameters for the molecules of substituted pheny lazides, 8 azidopyridines, 19 and azido 1,3,5 triazines. [20][21][22][23] As in phenylazides, 8 the azido groups in the molecules of compounds 1 and 5 slightly shift from the plane of the aro matic ring.…”

Synthesis and structure of 2,6-diazidotrichloropyridine N-oxide

“…Both azido groups are characterized by approximately similar C-N, N-N 2 , and N≡N bond lengths and CNN and NNN bond angles (see table). The torsion angles N 1 C 1 N 2 N 3 and N 1 C 5 N 5 N 6 characterizing deviation of the azido groups from the pyridine ring plane in molecule II are as small as 0.6 and 0.2°, respectively; i.e., they are considerably smaller that analogous dihedral angles (15.1-39.5°) in the molecules of known ortho-disubstituted azidopyridines [15][16][17]. A probable reason is formation of intramolecular contacts N 3 · · · O 1 (2.48 Å), N 6 · · · O 1 SYNTHESIS AND STRUCTURE OF 2,6-DIAZIDOTRICHLOROPYRIDINE N-OXIDE RUSSIAN (2.46 Å), N 4 · · · O 1 (2.98 Å), and N 7 · · · O 1 (3.00 Å), which fix the azido groups in the pyridine ring plane.…”

“…Furthermore, the azido groups in molecule II are characterized by anomalously small NNN bond angles (163.0 and 164.9°) and large CNN bond angles (122.2 and 122.8°), as well as by strongly shortened N-N 2 bonds [1.21(1) and 1.22(1) Å]. The corresponding parameters of α-azido groups in all α-azidopyridines, α-azidopyrimidines, and azido-1,3,5-triazines were on the average 172°, 112°, and 1.26 Å, respectively [15][16][17][18][19][20]. It was shown previously that the reactivity of azido group in 1,3-dipolar cycloaddition increases as the NNN bond angle decreases [21].…”