Phosphorus azides, photolysis

Photolysis of pentacoordinate pentavalent phosphorus azides leads to a Curtius-type reaction36,66. Further investigations into the photolytic behaviour of 25-phosphorus azide derivatives showed that three reaction types can be observed, depending on the nature of the substituents (a) Curtius-type rearrangement (b) tautomeric equilibrium between cyclic and open azides and (c) hydrogen abstraction reaction66. 

Photolysis of phosphorus azides invoTving a Curtius rearrangement seems to be a promising way for generating new metaphospho-nimidates species J. n... 

Efforts towards stabilization of metaphosphonimidates with bulky substituents failed. Photolysis of 5 at low temperature did not allow us to stabilize or ]. Irradiation of y in benzene gave rise to dimers and polymers but also to the hydrogen abstraction product. Moreover we did not succeed at the present time in the preparation of the phosphorus azide 2 from 8 certainly because of steric hindrance. 

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