Diphenyl-diazene

Likewise, thermolysis of 4-azidophenyl methyl ketone in methanol yields 5-acetyl-2-methoxy-3//-azepine (60%), compared to only an 8% yield from the photolytic reaction.78 119 The thermolysis of phenyl azide in refluxing cyclohexanol yields no 3H-azepine, only diphenyl-diazene (10%) and aniline (30%).74 In contrast, thermolysis of methyl 2-azidobenzoate in cyclohexanol furnishes a mixture of methyl 2-(cyclohexyloxy)-3//-azepine-3-carboxylate (20 % bp 127°C/0.1 Torr) and methyl 2-aminobenzoate (60%). Thermolysis of the azido ester in methanol under nitrogen in an autoclave at 150 C yields a 7 10 mixture (by 1HNMR spectroscopy) of the amino ester and methyl 2-methoxy-3//-azepine-3-carboxylate, which proved to be difficult to separate, and much tar.74 The acidic medium179 is probably responsible for the failure of methyl 2-azidoberjzoate to yield a 3//-azepine when thermolyzed in 3-methoxyphenol aniline (40%) is the major product.74... 

The reaction of norbomene with diethyl and diphenyl diazenedicarboxylate and dibenzoyl-diazene gives e.vo-oxadiazines 1 with unspecified yields25. The absence of rearranged products was assessed by experiments on 2,3-dideuterionorbornene. However, at least three other unidentified products were observed in the crude reaction mixture obtained with diethyl diazenedicarboxylate26. 

To a cold (0 "C), magnetically stirred solution of 4,4-dimethyl-3,5-diphenyl-3i/-pyrazole (2.4 g, 10 mmol) and cyclobutadieneirontricarbonyl (1.92 g, 10 mmol) in acetone (125 mL) under Nj was added ceric ammonium nitrate (27.4 g, 50 mmol) in portions over 30 min. The resultant slurry was poured into anhyd EtjO and the precipitated cerium salts were removed by filtration. The filtrates from two identical runs were evaporated and the combined crude product chromatographed (silica gel, EtjO/hexane 1 9). Recrystallization (hexane) gave 7,8-diaza-eui7o-9,9-dimethyl-l,6-diphenyltricyclo[4.2.1.0 ]nona-3,7-diene(9) as white crystals yield 4.09 g (68%) mp 153-154 "C (dec.). A solution of the diazene 9 (100 mg, 0.33 mmol) in EtjO (2 mL) was irradiated for 3 h with a 200-W Hanovia lamp (Pyrex filter). The progress of the reaction was monitored by TLC. Removal of the solvent gave 10 yield 90 mg (100%) mp 65-67 C. 

CAS 495-48-7 EINECS/ELINCS 207-802-1 Synonyms Azobenzene, oxide Azoxybenzide Azoxydibenzene Benzene, azoxydi- Diazene, diphenyl-, 1-oxide... 

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