Alkanes dimerization

Figure 5.1 Mass spectral results Summation spectral results at temperatures (a) 30 °C (6) 90-120 (c) 210-330 (rf) 330-780 °C — indicating the most prominent peak corresponding to the PCU alkane dimer and the presence of the m/z = 476 at the higher temperature setting and (e) the abnndances of the peaks at m/z = 81, 236, and 316 as a function of the scan number...

Degradation products from the diluent (Figure 8.1, Compounds A and B). Compounds A include alkane dimers and fragments of dodecane. Compounds B result from nitration and oxidation of the diluent. These nitration and oxidation reactions arise from the actions of HN03, 02, H20, and their radiolysis products on organic components. 

The facile oxidation of hydroxylamine and its derivatives with periodate has led to the suggestion that the method be used as a sensitive diagnostic test for the presence of the secondary hydroxamic acid link (43). The amM of the alkane dimers at 2670 A is close to 10, i. e., about ten times the absorbancy of ferric monohydroxamate at 5100 A. It should be noted that other attempts to increase the sensitivity of hy-droxamate determination have taken advantage of the relative alkali... 

Estimated MP2 and CCSD(T) interaction energies of w-alkane dimers at the basis set limit Comparison of the methods of Elelgaker et al. and Feller ... 

Alkane functionalization on a preparative scale by mercury-photosensitized C-H bond activation has been recently developed by Crabtree [22], Mercury absorbs 254-nm light to generate a Pi excited state which homolyzes a C-H bond of the substrate with a 3° > 2° > 1° selectivity. Radical disproportionation gives an alkene, but this intermediate is recycled back into the radical pool via H-atom attack, which is beneficial in terms of yield and selectivity. The reaction gives alkane dimers and products of cross-dehydrodimerization of alkanes with various C-H compounds ... 

Mercury sensitized reactions of alkanes have been extensively studied in the context of C—H bond activation. It has been observed that many alkane dimerizations can be carried out photochemically on a preparative scale with high conversion and excellent yields (equations 115 and llb) " . ... 

A photoprocess that may involve the formation rather than the cleavage of metal-hydrogen or metal-carbon bonds is the mercury-photosensitized dehydrodimerization or the alkane functionalization reaction. The reaction involves the coupling of an alkane to give the alkane dimer and hydrogen ... 

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