Cyclohexyl azide, decomposition

Kwart and Khan investigated the copper-catalyzed decomposition of benzenesulphonyl azide both in methanol 33) and in cyclohexene 34>. No reaction occurs between benzenesulphonyl azide and cyclohexene at 100 °C but the addition of copper powder causes a smooth decomposition to take place yielding an impressive array of products 34>. The major ones are benzenesulphonamide 18 (37%), the aziridine 19 (15%) and the lV-(l-cyclohexenyl)benzenesulphonamide 20 (17%) (Scheme 2). Some traces of cyclohexyl azide were also found but the addition of hydro-quinone eliminated its formation. 

The heats of formation of various azides were determined firom their heats of combustion and decomposition (some of the data are collected in reference 1). The heats of formation of HN3, cyclopentyl azide and cyclohexyl azide were compared with those calculated for the canoni-... 

Decomposition of aUcyl azides with aluminium chloride in benzene at 50° gave products which corresponded to the formation of a carbonium ion (loss of N3 ) and to an electron-deficient nitrogen (loss of N2) . For example, cyclohexyl azide gave phenylcyclohexane (30%), cyclohexanone imine (90) (15%) and the ring-expanded imine (91) (30-40%). The same workers reported the first example of an aUcyl nitrenium ion being trapped by benzene in reasonable yieldIn the presence of three equivalents of aluminium chloride in benzene, azidoacetone (92) gave the aromatic substitution product (93) in 35%... 

Walker and Waters considered the effects of various solvents on the rates of decomposition of phenyl, /(-methoxyphenyl and cyclohexyl azides and on the nature of the products obtained. Some of their results are summarized in Table 4. The decompositions could... 

The copper-catalysed decomposition of benzenesulphonyl azide in cyclohexene gave a variety of products (equation 182) . In the presence of hydroquinone, cyclohexyl azide was not observed. It was assumed that cyclohexanone came from the hydrolysis of the imine (405). The copper-catalysed decomposition of 2-biphenylylsulphonyl... 

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

Boyer and co-workers studied the sulphuric acid-catalysed decomposition of three secondary cyclic azides cyclopentyl, cyclohexyl and cycloheptyl, and found that ring expansion, i.e. alkyl migration, competes quite favourably with hydrogen migration. For example, cyclopentyl azide in chloroform, gave cyclopentanone (as its 2,4-dinitrophenylhydrazone, 2-2%) and piperideine (5) (79 8%), on... 

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