A Hydrogen Abstraction Reaction

The cancellation in GP effects in the state-to-state DCS are found [20-22, 26, 27, 29] at low impact parameters, when F(J) in Eq. (15) is chosen to include only contributions for which / < 9. It is well known [55,56] that most of the reactive scattering in this regime consists of head-on collisions, in which the reaction proceeds mainly by the H atom striking the H2 diatom at geometries that are close to linear. Most of the products are then formed by direct recoil in the backward (9 = 180°) region, this being typical behavior for a hydrogen-abstraction reaction. 

Imido alkylidene complexes were first prepared by a reaction analogous to that shown In equation 6. Recently they have been prepared from imido alkyl complexes by well-behaved a-hydrogen abstraction reactions (16) Imido neopentylidene complexes seem to be more stable than oxo neopentylidene complexes, possibly because the oxo ligand is sterically more accessible to Lewis acids, including another tungsten center. 

Mo and W alkylidene complexes usually are prepared from M(VI) dialkyl complexes by some variant of the a hydrogen abstraction reaction (Eq. 7 other ligands omitted) [5,41]. 

Under oxidizing conditions some additional pathways open up for the conversion of the chlorinated hydrocarbons. First step is typically a hydrogen abstraction reaction, for example,... 

Basuli, F., Bailey, B.C., Huffman, J.C. and Mindiola, D.J., (2005) Intramolecular C-H activation reactions derived from a terminal titanium neopentylidene functionality. Redox-controlled 1,2-addition and a-hydrogen abstraction reactions. Organometallics 24, 3321. 

A hydrogen abstraction reaction also likely occurred generating the five-line component. Accordingly, the mechanisms are illustrated in equations 2, 3 and 4. 

Acetic acid was found by Caldwell and Hoare31 in the later stages of a chain reaction presumably due to a hydrogen abstraction reaction at 200°C. They agree with Brown et al.87 that little is formed at lower... 

Another kind of approach is based on estimates from first principles. The fundamental concept of these approaches is that the E of a hydrogen abstraction reaction will be determined mainly by the strength of the C-H and H-X bonds and by repulsions between R3C and X in the transition state. 

Other (neutral) tantalum alkylidyne complexes formed by a hydrogen abstraction reactions followed, [33,34] although the alkylidyne ligand became much more prominent in the chemistry of Mo, W, and Re. 

Evaluated In a photoionization mass spectrometric study from the difference in the thresholds for PHJ from PH3 and PHJ from PHg [1 ]. This value is only 4 kJ/mol higher than the almost coincident values calculated with the 4th-order Moller-Plesset perturbation procedure [1, 8] and with the generalized valence bond model [9]. - From the electron impact ionization of PH3 and PHg. - From the fluorescence excitation of PH3 photolysis fragments. - From the appearance potential of PHJ in electron impact studies of PH3 and the ionization potential of PHg. - From the appearance potential of PH2 from PH3 (2.2,2.3 eV) and the electron affinity of the PH2 radical (1.25 eV, see p. 62) [5] for earlier results (D<326 kJ/mol), see [10]. - From the highest populated rotational-vibrational level of HF, which is produced in a hydrogen abstraction reaction of PH3 with F atoms in a flowing afterglow experiment [6] for earlier results, see [11]. - Literature value based on the upper limit D<326 kJ/mol. 

Chain transfer and radical disproportionation are similar in that both involve a hydrogen abstraction reaction. 

Clearly this cannot be correct. It is also true that if the reaction is very ineffective, then there should be no (n) dependence since each reactant molecule will encounter the same number of polymer bound chromophores since the mole fraction of these chromophores in solution is held constant. An example of this behavior has been provided recently by Winnik and Maharaj (42) for n-alkanes (n from 6 to 36) undergoing a hydrogen abstraction reaction with triplet benzo-phenone. 

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