Nitric oxide reactions with alkenes

A convenient preparative method for conjugated nitroalkenes has been developed based on the reaction of nitrogen oxides. Nitric oxide (NO) is commercially available and used in the industry for the mass production of nitric acid. Nitric oxide is currently one of the most studied molecules in the fields of biochemistry, medicine, and environmental science.47 Thus, the reaction of NO with alkenes under aerobic conditions is of a renewed importance.48... 

Much evidence has been accumulated that the ozone-olefin reaction has a predominant role in aerosol formation from alkenes, cyclic olefins, diolefins, and other unsaturated compounds. Free radicals are formed in the reaction and can react further, along with nitric oxide and nitrogen dioxide, either with the various intermediates or with the olefin itself (see the recent review by Pitts and Finlayson ). 

A very remote secondary H/D isotope effect has been measured for the 2 + 2-cycloaddition of TCNE to 2,7-dimethylocta-2,fran -4,6-triene. The reaction of nitric oxide with iV-benzylidene-4-methoxyaniline to produce 4-methoxybenzenediazonium nitrate and benzaldehyde is thought to proceed via a 2 + 2-cycloaddition between nitric oxide and the imine double bond. A novel mechanism for the stepwise dimerization of the parent silaethylene to 1,3-disilacyclobutane involves a low-barrier [1,2]-sigmatropic shift. Density functional, correlated ab initio calculations, and frontier MO analysis support a concerted 2 + 2-pathway for the addition of SO3 to alkenes. " The enone cycloaddition reactions of dienones and quinones have been reviewed. The 2 + 2-photocycloadditions of homochiral 2(5H)-furanones to vinylene carbonate are highly diastereoisomeric. ... 

The reaction of fuming nitric acid with 2-methyl-2-butene (3) is reported to yield 2-methyl-3-nitro-2-butene (4). The reaction of alkenes with fuming nitric acid, either neat or in chlorinated solvents, is an important route to unsaturated nitrosteroids, which assumedly arise from the dehydration of /3-nitroalcohols or the elimination of nitric acid from /3-nitro-nitrate esters. Temperature control in these reactions is important if an excess of oxidation by-products is to be avoided. 

Park J. S. B., Walton J. C. Reactions of nitric oxide and nitrogen dioxide with functionalised alkenes and dienes. J. Chem. Soc., Perkin Trans. 2 1997 2579-83. 

Preparation of nitronitroso dimers from a variety of straight chain alkenes has been patented. " The reactions of nitric oxide with alkenes are extremely complex (e.g. isobutylene) and are rarely usefiil. Perfluoroalkenes add nitric oxide at room temperature in the da tetraflucMoethylene gives ONCF2CF2NO (68%) the reaction with perfluoropropene is more complex. ... 

The reaction of alkenes with nitric oxide (NO), a mixture of nitric oxide and oxygen, or dinitrogen trioxide leads to /i-nitroso nitro compounds ( / -nitrosites or pseudo-nitrosites), which can convert to nitroso dimers79. Nitroalkenes are common byproducts in these reactions. The formation of /i-nitroso nitro compounds in the reaction between alkenes and nitric oxide is explained by the presence of nitrogen dioxide and dinitrogen trioxide in the nitric oxide. The reaction may be initiated by the attack of the N02 radical on the alkene to give a /i-nitroalkyl radical which then couples with nitric oxide. 

The reaction of alkenes with pure nitric oxide, however, occurs only at a pressure of 5 atmospheres or more, affording the /i-nitroso nitro compounds in rather low yields together with more complex unidentified materials80. Under these conditions it is presumed that initial disproportionation of nitric oxide occurs. 

Jennings and coworkers " were the first to report on a mass spectrometric method of locating double bonds by use of gas-phase ion/molecule reactions. Ionized alkyl vinyl ethers proved to be highly suitable reagent ions, and the principle of this gas-phase method for double-bond localization is illustrated for prototype dienes 76-78 in Scheme 22. At the same time. Hunt and coworkers introduced nitric oxide (NO) as a reagent gas in Cl mass spectrometry and studied the reactions of the NO+ and [NONO]+ ions with alkenes and also with several acyclic dienes and 1,3,5-cycloheptatriene. Thereafter, several groups have contributed to the development and only some classical work concerning simple alkenes may be mentioned here. 

Tg yr. Miscellaneous other reactions, such as the reaction with nitric oxide or that with alkenes, take up another 200 Tg yr, approximately. The total amount of ozone removed by chemical reactions is 3450 Tgyr . The excess of photochemical production over losses by chemical reactions is 750 Tgyr which is of the same magnitude as the influx from the stratosphere. The residence time of ozone in the troposphere, which is determined by the average concentration and the sum of all sources, is about 20 d. As the turnover is dominated by photochemical processes, the local lifetime depends on latitude and season. Winter lifetimes can be considerably longer, and tropical lifetimes are shorter. 

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