Alkyl nitrites thermal decomposition

Thermal or photo-induced decompositions of dialkyl peroxides in the presence of suitable substrates yield various products. For example, with nitric oxides, alkyl nitrites or nitrates are formed and, with carbon monoxide, Z fZ-alkyl esters are obtained (44) ... 

The synthesis of the triptycene system illustrates a synthetic use of the important reactive intermediate benzyne (13) which is generated by the thermal decomposition of benzenediazonium-2-carboxylate (see Section 6.5.3, p. 900). The latter is produced when anthranilic acid (11) is treated with an alkyl nitrite in an aprotic solvent, and probably exists mainly as the zwitterionic form (12). 

The use of the direct thermal decomposition method has been fairly widespread, and the values obtained by it will be discussed in the appropriate sections of this book. The O - N bond in alkyl nitrates and nitrites, and the G N bond in nitromethane are among those whose dissociation energy has been measured by this method, but in view of the possible kinetic complexities which may be encountered, such as those already mentioned in connection with the pyrolysis of organic iodides (see Section 4.2.4) the values obtained are often at best only tentative. 

The thermal decomposition of a series of alkyl nitrites has been studied by Steacie and co-workersThe primary step is almost certainly... 

Nitroso derivatives of hydrocarbons cannot be obtained by direct nitrosation, except under irradiation as mentioned above. They are prepared by oxidation of other nitrogenous groups (see p. 591), photochemical or thermal decomposition of alkyl nitrites,282 or, recently, by oxidative fission of oxaziridines.283... 

Williams, 1959 Gray et al., 1967 Heicklen, 1968 Howard, 1972), but no general update seems to have t peaied. However, Batt (1979) has reviewed the thermochemistry and thermal-decomposition kinetics for aikoxyl radicals and alkyl nitrites. It is the purpose of the present review to report all work through June, 1986 (and some later) on the reactions of alkoxy radicals. In addition, since aikoxyl radicals often are produced in laboratory experiments from alkyl nitrites, the photochemical and thermal decomposition of these species will also be reviewed. 

The thermal decomposition of alkyl nitrites was first studied by Steacie and Shaw (1934a). They showed that the decomposition of CH3ONO was homogeneous and unimolecular from 33.3 to 513.5 Torr and 190 to 241°C with a rate coefficient of 1.84 x 10 exp(-36.4// 7) sec . The overall stoichiometry of the decomposition was... 

Steacie and his coworkers examined the thermal decomposition of several other simple alkyl nitrites. Steacie and Shaw (1934b) studied C2H5ONO at 190-240°C. They found the reaction to be homogeneous and first-order with a rate coefficient of 1.39 x 10 " exp —37.7/R7 sec. There was no falloff in the rate constant for pressures down to 55 Torr. 

There appear to have been no further studies on the thermal decomposition of alkyl nitrites until 1949. Then two more complex nitrites were studied. Komblum and Oliveto (1949) examined the thermal decomposition of optically active 2-octyl nitrite in the liquid phase at 100°C. Optically pure r(-2-octanol was obtained in excellent yield, thus showing that 2-octoxyl radicals were produced, and that these did not racemize. 

Additional values of vere obtained by Morabito and Heicklen (198Sb). They examined the thermal decomposition of several alkyl nitrites in the presence of NO. By measuring the RO 0 and aldehyde produced they had a direct determination of k JIhb. Their results also are given in Table 8. 

One of the possible causes of the development of an oxidative course in the nitration lies in the thermal decomposition of nitrocompounds and alkyl nitrites [4]. RONO decomposes between 300 °C and 500 °C. For instance, ethylnitrite produces a free... 

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