Nitrosoarenes, aryl azides

Nucleophilic displacement of the butoxy group in 2-butoxy-3//-azepine (1) by the use of excess secondary amine is preferred by some workers64 to the photolysis or thermolysis of aryl azides, or the deoxygenation of nitro- or nitrosoarenes in amine solution, as a preparative route to Ar,Ar-dialkyl-3//-azcpin-2-amines, e.g. 2,... 

It is generally accepted that the mechanism of this trialkyl phosphite deoxygenation of nitroarenes involves initial transformation to the nitrosoarene and trialkyl phosphate followed by a second deoxygenation to the corresponding nitrene. Support for this pathway is seen by the fact that noatching aryl azides afforded similar product ratios under thermolysis conditions [10-12], Indeed, prior to the work of Cadogan and Sundberg, several workers described indole... 

Aryl Azides from Hydrazines and from Nitrosoarenes... 

An efficient synthesis of aryl azides can be achieved by the reaction of nitrosoarenes with hydrogen azide (Scheme 3.41). The drawback of this approach is that two equivalents of the explosive reagent is required since the process involves the initial formation of diazonium ions followed by the reaction with the azide ion. 

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