Oxidation 2,3-dimethylbutane product

Photolytic. Major products reported from the photooxidation of 2,3-dimethylbutane with nitrogen oxides are carbon monoxide and acetone. Minor products included formaldehyde, acetaldehyde and peroxyacyl nitrates (Altshuller, 1983). Synthetic air containing gaseous nitrous acid and exposed to artificial sunlight (A. = 300-450 nm) photooxidized 2,3-dimethylbutane into acetone, hexyl nitrate, peroxyacetal nitrate, and a nitro aromatic compound tentatively identified as a propyl nitrate (Cox et al., 1980). 

When a stream of oxygen containing 15% ozone was passed through a solution of isobutane in HSC F-SbFs-SOiClF solution held at —78°C, the colorless solution immediately turned brown in color. 1H and 13C NMR spectra of the resultant solution were consistent with the formation of the dimethylmethylcar-boxonium ion in 45% yield together with trace amounts of acetylium ion (CH3CO+). Further oxidation products (i.e., acetylium ion and C02) were reported to be observed in a number of reactions studied. Such secondary oxidation products, however, are not induced by ozone. Similar treatment of isopentane, 2,3-dimethylbutane, and 2,2,3-trimethylbutane resulted in formation of related carboxonium ions as the major products (Table 5.37). 

The gas phase oxidation of 2,3-dimethylbutane (Table 7, entry 51) leads to number of products even under mild conditions [56], The selectivity of alkane oxidations, e.g. methane oxidation (Table 7, entry 52) increases substantially in the pres-... 

Four other alkanes were photolyzed in the presence of nitrous oxide principally to determine the yield of N2. In all four cases < (N2) was less than for cyclohexane solutions (Table II and Figure 1). For cyclopentane and 2,2-dimethylbutane < (N2) at 68 mM N20 is only 0.04, which is 10% of the yield of N2 for cyclohexane. For 2,2,4-trimethylpen-tane solutions (N2) is also low, and (CH4), a major product, is unaffected by N20. n-Hexane seems to be an intermediate case with respect to No formation like cyclohexane ( N2) + < ( H2) 1 here too. 

At high-temperature conditions, the product distributions of typical decar-boxylative and aldol condensations vary with temperature, time on stream, and catalyst age. Several ketone isomers can be produced. With acetic acid, e.g., C5-C7 (e.g., methylhexanone, pentan-2-one, 3,3 -dimethylbutan-2-one) ketones and alkylphenols arise from acetone aldolization. An important cyclic product in low temperature acetone aldolization is isophorone (2-cyclohexen-l-one, 3,5,5 -trimethyl), formed by the aldol condensation of acetone with mesityl oxide, followed by 1,6-Michael addition. In reactions with acetic acid, we have observed 2-cyclohexen-l-one, 3,5-dimethyl, which is probably a cracking product of isophorone, and small amounts of isophorone itself. Cracking to produce... 

Grignard reaction with formaldehyde closer to our desired product. Subsequent hydrolysis will yield 2,2-dimethylbutanol our desired product is 2,2-dimethylbutanal. Oxidation of the primary alcohol to the aldehyde can be accomplished with Sarett s reagent, a combination of chromium trioxide (CrOs) with pyridine. 

The formation yields for alkene production in the OH initiated oxidation of a number of saturated hydrocarbons (alkanes) have been determined. The 254 nm photolysis of H2O2 was employed as the OH source and GC-MS for detection of the products. The following alkanes were investigated n-butane, n-pentane, 2,3-dimethylbutane and cyclopentane. 

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