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Reactions of various arylamines with either t-butyl thionitrite, t-butyl thionitrate, or p-toluenesulfonyl nitrite in the presence of anhydrous copper(II) halides under mild conditions gave corresponding aryl halides in good yields. This reaction in the presence of such olefins as acrylonitrile, styrene, and acrylic acid gave the corresponding 2-aryl-1-haloethanes as the main products. t-Butyl thionitrite, t-butyl thionitrate, and p-toluenesulfonyl nitrite were found to be better deaminative reagents than alkyl nitrites or alkyl nitrates due to their weak sulfur–nitrogen bonds.

The rate of decomposition of isopropyl nitrite (IPN) has been studied in a static system over the temperature range of 130–160°C. For low concentrations of IPN (1–5 × 10−5M), but with a high total pressure of CF4 (∼0.9 atm) and small extents of reaction (∼1%), the first-order rates of acetaldehyde (AcH) formation are a direct measure of reaction (1), since k3 » k2(NO): Addition of large amounts of NO (∼0.9 atm) in place of CF4 almost completely suppressed AcH formation. Addition of large amounts of isobutane – t-BuH – (∼0.9 atm) in place of CF4 at 160°C resulted in decreasing the AcH by 25%. Thus 25% of were trapped by the t-BuH (4): The result of adding either NO or t-BuH shows that reaction (1) is the only route for the production of AcH. The rate constant for reaction (1) is given by k1 = 1016.2±0.4–41.0±0.8/θ sec−1. Since (E1 + RT) and ΔH°1 are identical, within experimental error, both may be equated with D(i-PrO-NO) = 41.6 ± 0.8 kcal/mol and E2 = 0 ± 0.8 kcal/mol. The thermochemistry leads to the result that From ΔS°1 and A1, k2 is calculated to be 1010.5±0.4M−1·sec−1. From an independent observation that k6/k2 = 0.19 ± 0.03 independent of temperature we find E6 = 0 ± 1 kcal/mol and k6 = 109.8+0.4M−;1·sec−1: In addition to AcH, acetone (M2K) and isopropyl alcohol (IPA) are produced in approximately equal amounts. The rate of M2K formation is markedly affected by the ratio S/V of different reaction vessels. It is concluded that the M2K arises as the result of a heterogeneous elimination of HNO from IPN. In a spherical reaction vessel the first-order rate of M2K formation is given by k5 = 109.4–27.0/θ sec−1: IPA is thought to arise via the hydrolysis of IPN, the water being formed from HNO. This elimination process explains previous erroneous results for IPN.

It is shown that it is possible to obtain good data for the rate constant for the decomposition of alkoxy radicals [RO] by using nitric oxide as a radical trap. Two experimental systems have been used. The first system involves the use of dialkyl peroxides [(RO)2] as thermal sources of alkoxy radicals. The peroxide concentration was ∼10−4M, nitric oxide ∼2 × 10−4M, and the extent of reaction was ∼10%. The total pressure was altered using carbon tetrafluoride as an inert gas. The mechanism is Hence R2/R3 = k2[NO]/k3. Our previous studies show that k2 lies in the range 1010.3±0.2M−1·sec−1. The second system employs alkyl nitrites [RONO] as a thermal source of alkoxy radicals. The experimental conditions are very similar, except that we chose to use an atmosphere of nitric oxide for initial experiments. If anything nitric oxide appears to be superior to carbon tetrafluoride as an energy transfer agent. The mechanism is Hence R3 = k1'k3[RONO]/(k3 + k2 + k6 [NO]). Results are given for R = t-Am, s-Bu, t-Bu, i-Pr, Et, and Me. In addition the first unequivocal evidence is given for the pressure dependence of k3 when R = t-Bu. The implications for atmospheric chemistry and combustion are also discussed.

Oxidative deamination of unbranched primary amines by the combination of alkyl nitrites and anhydrous copper(II) halides in acetonitrile produces geminal dihalides selectively and in synthetically useful yields.

Les temps de relaxation pour la conversion intramoleculaire (syn⇄anti) des alkylnitrites est mesuree par spectroscopie RMN dynamique en solution et a l'etat gazeux. Cinetique