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Analysis of the products indicates that at temperatures below –5°, the reaction of diethyl ether with copper(II) nitrate yields exclusively gaseous ethyl nitrite and complexed acetaldehyde. At higher temperatures, the acetaldehyde is further oxidised to acetate, with liberation of gaseous NO and NO2. Molecular mechanisms, not involving the NO3 radical, are suggested.

A novel displacement of certain activated aromatic nitro-groups by tervalent organophosphorus reagents is described. Thus trimethyl, triethyl, and tri-isopropyl phosphites, diethyl methylphosphonite, and ethyl diphenyl-phosphinite react with increasing ease [(RO)3P < (EtO)2PMe < EtOPPh2] with o-dinitrobenzene to give high yields of the corresponding dialkyl o-nitrophenylphosphonates, ethyl P-methyl-o-nitrophenylphosphinate, and o-nitrophenyldiphenylphosphine oxide, respectively, and ethyl nitrite. 1,2,4-Trinitrobenzene undergoes similar displacements to give 2,4-dinitrophenyl derivatives. Under comparable conditions p-dinitrobenzene and o-chloronitrobenzene do not undergo these reactions other than, possibly, to a very minor extent.

IN the hope of trapping the radicals probably produced during the photolysis of diethyl peroxide, the vapour of the latter was mixed with a several-fold excess of nitric oxide in a 3-litre ‘Pyrex’ bulb. The mixture was then passed through a water-cooled helical silica tube surrounding a mercury arc into a trap immersed in ‘Drikold’. Suspiciously large amounts of ethyl nitrite were found in the trap, and even larger quantities were collected in a blank run without the arc. After the mixture had been stored in the dark for twenty-four hours, spectrophotometric examination showed that a major portion of the peroxide had been converted into nitrite.

The occurrence of bimolecular nucleophilic aromatic substitution has been established in the reaction of o-dinitro-benzene with triethyl phosphite and diethyl methylphosphonite in acetonitrile solution. The role of the o-nitro-group in facilitating the nucleophilic substitution has been discussed in terms of ‘built-in solvation’ of the reaction centres. The exclusive formation of ethyl nitrite in the reactions has been shown to be compatible with the dealkylation of a quasi-phosphonium intermediate by nitrite ions.