Benzyl azide, decomposition

Whereas nitrosative decomposition of azidoalkanes such as hexyl, cyclohexyl, and benzyl azides with nitrosomum tetrafluoroborate gives only 0-5% yields of... 

The thermal formation of a nitrene has been invoked to account for the result in the reaction between a sterically hindered thioketene and benzyl azide437 (equation 123). Although initially a 1,3-dipolar cycloaddition between the C=S bond and the azide was expected, the temperature of the reaction (138 °C) led to decomposition of benzyl azide into benzyl nitrene and the subsequent [2 + 1] cycloaddition. 

The thermal decomposition of adducts of A-phenylmaleimide and A-phenylcitraconimide with benzyl azides to yield aziridines via the loss of N2 has been studied by thermogravimetric and differential scanning calorimetric methods. It was found that the decomposition of the triazolines (60a-d) depends upon the nature of the para-substituent on the benzyl moiety. Also, the methyl... 

This method has been exploited for the functionalization of [60]fullerene by using several aroyl azides166 and [2.4,6-tri-(tm-butyl)phenyl]oxycarbonyl azide16, which afforded the corresponding A -acylaziridines and subsequently the dihydrooxazoles, whereas azafulleroids were produced with [2-(trimethylsilyl)ethoxy]methyl azide and several benzylic azides presumably through the thermal decomposition of the intermediate dihydrotriazoles77. 

The decomposition of benzyl azide is very complex and the thermolysis, at least, seems to involve more than one primary process. The pyrolysis in diphenyl ether results in the formation of 2,4,5-triphenylimidazole (I), 2,4,6-triphenyl-1,3,5-triazine (II) and iV-benzylidenebenzylamine (III)... 

Gurtius and co-workers studied the acid-catalysed decomposition of alkyl azides such as benzyl azide. This was decomposed in either warm 1 1 (v/v) sulphuric acid-water or with concentrated hydrochloric acid to give a mixture of products corresponding to hydrogen migration [benzaldiinine (1)], phenyl migration [formaldehyde anil (2)], the azide reduction product [benzylamine (3)], and the solvolysis product [benzyl alcohol (4)]. The first two were obtained as the... 

The cycloaddition of aryl, benzyl, and 1-phenylethenyl azides to strained bicyclic alkenes, e.g., norbornene, and their substituted derivatives afforded generally the exro-dihydrotriazoles 17, which on photolytic decomposition afforded cleanly the exro-aziridines 233,42-48,70,93. Thermal decomposition of the dihydrotriazoles resulted in a complex mixture of products, including both exo- and entfo-aziridine and the imine95,96. 

Unlike the photolysis of alkyl and aryl azides, photolytic decomposition of sulphonyl azides in solvents such as cyclohexane, cyclohexene, benzyl alcohol, pyridine and thiophene gives insoluble polymeric... 

More recently, the same catalyst was used to produce cyclic amines with retention of stereochemistry from a simple linear aliphatic azide [53]. Treatment of a substituted aliphatic azide by complex 66 afforded the cyclized compound 75, by insertion of the nitrene moiety in allylic, benzylic, and even in the less reactive tertiary C—H bonds. The catalyst is inhibited by coordination of the product to the metal center. However, that can be avoided by using an in situ protecting agent (Boep is preferred over Fmoc-OSuc which leads to catalyst decomposition). 

Typical Procedure. Benzyl N-vinyl carbamate 810 [590]. Note Some of the chemicals described bdow can undergo rapid decomposition and polymerization, with evolution of gaseous products. Acryloyl azide in neat form may be dangerously explosive, and vinyl isocyanate is probably very toxic. AU experiments should be carried out behind a safety shield in a weU-ventdated hood. Extreme care should be taken to avoid injury. 

In 2007, cobalt(II)-tetraphenylporphyrin (TPP) complex was reported to be a competent catalyst for intramolecular amination of benzylic C-H bond through decomposition of sulfonyl azide (Scheme 10.19) [48]. Thus, arylsulfonyl azides... 

---