Carbon bond dissociation

Carbon-carbon bond dissociation energies have been measured... 

Cleavage of the carbon-carbon bond in ethane yields two methyl radicals whereas propane yields an ethyl radical and one methyl radical Ethyl radical is more stable than methyl and so less energy is required to break the carbon-carbon bond in propane than in ethane The measured carbon-carbon bond dissociation energy in ethane is 368 kJ/mol (88 kcal/mol) and that in propane is 355 kJ/mol (85 kcal/mol)... 

Examples of silver(l) alkyl and alkenyl (including aryl) complexes have been known from as early as 1941 6-9 however, the number of examples is fairly limited with respect to that of the heavier congeners, copper(l) and gold(l). Such a phenomenon can readily be attributed to the relatively low stability of this class of complexes, both photochemically and thermally. Simple homoleptic alkyl and alkenyl complexes of silver(i) are known to be very unstable under ambient temperature and light, and successful isolation of this class is fairly limited and mainly confined to those involving perfluoroorganics.10 The structures and the metal-carbon bond-dissociation energies for... 

The thermal decomposition is first-order and the rate coefficient is given by k = 1.7 x 1014 exp(—51,000/i T) sec-1. The mean metal-carbon bond dissociation energy in this alkyl is 58.0 kcal.mole-1. In view of the normal frequency factor, it might seem reasonable to relate the observed activation energy to... 

Fig. 19. Pt/Cu alloys in interaction with 3C complexes. Speculation on various positions in which the 3C complexes interact with both alloy components, Cu being involved either in binding (a, b) or hydrogen-carbon bond dissociation.

As noted in part (b), a secondary radical is produced on carbon-carbon bond cleavage of 2-methylpropane. We therefore expect a lower carbon-carbon bond dissociation energy for 2,2-dimethylpropane than for 2-methylpropane, since a tertiary radical is more stable than a... 

Silicon-carbon bond dissociation energies are less than those of C—C bonds but are still quite high, in the region 250 to 335 kJ mol 1. The tetraalkyls and -aryls are hence thermally quite stable Si(QH5)4, for example, boils unchanged at 530°C. 

Table 1. Carbon-carbon bond dissociation energies BDEc-c) in neutral compounds and their radical cations [kjmol" ]. Data are gas-phase numbers from thermochemical cycle calculations by Dinnocenzo [22]...

Yee A, Morrison SJ, Idriss H (2000) The reactions of ethanol over M/CeO catalysts Evidence of carbon-carbon bond dissociation at low temperatures over Rh/CeO. Catal Today 63 327... 

Thermodynamic aspects of the insertion reactions have been considered, especially with regard to reactions (b), Y = O. The enthalpy change of the reaction is related to the disruption of the metal-carbon bond, the formation of the new metal-carbon bond, the formation of the new carbon-carbon bond, and the reduction of the CO bond order. From the estimated metal-carbon bond dissociation enthalpies (BDE) of reagent and product and from the energetics of the other quantities involved in the process, the AC of reaction (g) has been calculated to be negative for R = Me or Ph and positive for R = CF3. This is in agreement with the observation that the trifluoroacetyl derivative... 

PROBLEM 4.16 Carbon-carbon bond dissociation energies have been measured for alkanes. Without referring to Table 4.3, identify the alkane in each of the following pairs that has the lower carbon-carbon bond dissociation energy, and explain the reason for your choice. 

The transformation of a radical-cation into a radical involves processes such as carbon-hydrogen dissociation, carbon-metal bond dissociation, carbon-carbon bond dissociation (this latter process is not frequently encountered and will not be treated in this review) and nucleophilic addition. 

Determination of Cobalt-Carbon Bond Dissociation Energies... 

COBALT CARBON BOND ENERGIES. The cobalt-carbon bond dissociation energy has been reported (18) for a series of base adducts of alkyl-substituted bis (dimethylglyoximato) cobalt(II),... 

Mo1vbdenum-Carbon and Niobium-Carbon Bond Dissociation Enthalpies... 

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