Ethane exposion properties

The effect of microwave irradiation on the catalytic properties of a silver catalyst (Ag/Al203) in ethane epoxidation was studied by Klimov et al. [91]. It was found that on catalyst previously reduced with hydrogen the rates of both epoxidation and carbon dioxide formation increased considerably on exposure to a microwave field. This effect gradually decreased or even disappeared as the catalyst attained the steady state. It was suggested that this was very likely because of modification of electronic properties of the catalyst exposed to microwave irradiation. 

The presence of the k bond confers properties on an alkene that mark it out as different from an alkane. In particular, the n bond, by the nature of its sideways overlap of the constituent p orbitals, is weaker than a a bond. Moreover, the electrons of the n bond are relatively exposed, above and below the plane of the alkene. These electrons are the source of reactivity of the alkene toward electrophiles, as in, say, electrophilic addition of bromine (Chapter 4). The n bond in ethene (and other alkenes) is, however, sufficiently strong that it prevents rotation around the carbon-carbon a bond, which is a well-documented property of the carbon-carbon bond in ethane (Section 1.6). The bonding between sp2... 

About a century ago, Gomberg attempted to prepare hexa(phenyl)ethane(2) by treating a solution of triphenylmethyl chloride (1) with silver or zinc. He obtained a yellow solution of a stable species whose properties, though, did not appear compatible with those expectedfrom a hydrocarbon like hexa(phenyl)ethane. For example, the solution would decolorize rapidly when exposed to air, or treated with iodine or a number of other materials known to react with organic radical. Gomberg concluded in his paper of 1900 [1] The experimental evidence forces me to the conclusion that we have to deal here with a free radical, triphenylmethyl, (C6Hy)sC (3) ( Scheme ). 

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