Synthesis and study of new 2-aryl-1-(4-nitrophenyl)-1,1a-dihydroazireno[1,2-a]quinoxaline derivatives

Abstract

New derivatives of photochromic 2 aryl 1 (4 nitrophenyl) 1,1a dihydroazire no[1,2 a]quinoxalines were synthesized by condensation of 4 methyl and 4,5 dimethyl 1,2 phenylenediamine with 1,3 diaryl 2,3 dibromopropan 1 ones. The reactions of 4 methyl 1,2 phenylenediamine produce mixtures of regioisomers. The chemical properties of the reac tion products were studied. The structure of one of the latter was established by X ray dif fraction.Key words: 1,3 diaryl 2,3 dibromopropan 1 ones, 1,2 diaryl 1,1a dihydroazire no[1,2 a]quinoxalines, 2 arylquinoxalines, 4 aryl 1,2 bis(4 nitrophenyl) 1,2 dihydro 3aH oxazolo[3,2 a]quinoxalines, X ray diffraction study.

Synthetic Utilization of α,β‐Chalcone Dibromide In Heterocyclic Chemistry and Stereoselective Debromination

“…Chebanov and co‐workers disclosed another convenient and straightforward synthesis of photochromic 2‐aryl‐1‐(4‐nitrophenyl)‐1,1a‐dihydroazireno[1,2‐ a ]quinoxaline derivatives 17 and 18 by utilization of α,β‐chalcone dibromides 2 and methyl substituted o‐phenylenediamines 16 in presence of triethylammine in methanol (Scheme ) …”

“…and 18 by utilization of α,β-chalcone dibromides 2 and methyl substituted o-phenylenediamines 16 in presence of triethylammine in methanol (Scheme 9) [36]. .Scheme 4.…”

Fused aziridines as sources of azomethine ylides

“…Thus, refluxing of 1,4-diaza[4.1.0]hex-4-enes 16 in toluene in the presence of various dipolarophiles led to formation of the corresponding adducts 18 [12]. Reaction of the azomethine ylides 17 and 20 with benzaldehydes takes place regioselectively, leading to derivatives of oxazolo[3,2-a]quinoxaline 18 and 21 [12,13] By the thermolysis of aziridines fused with seven-membered rings at the C-N bond in the presence of various dipolarophiles it is possible to synthesize (5,7)-bicyclic heterocycles. Refluxing of the azirinobenzodiazepine 22 in xylene in the presence of fumaronitrile leads to the stereoselective formation of the 1,5-diazabicyclo [5.3.0]deca-3,5-diene derivative 24 [14].…”