Olefin hydrogenation background

Olefin Hydrogenation with Wilkinson s Catalyst 2.2.1. Background and Rate Laws... 

Background. The Wilkinson Rh complex, RhCl[P(C6H5)3]3, catalyzes the hydrogenation of simple olefins in organic solvents under mild conditions. The mechanism which involves the oxidative addition of H2 to Rh(I) is shown in Scheme 2 (5-7). 

Markownikoff s rule states that during the addition of H X to an asymmetrically substituted olefin the negative part becomes attached to the unsaturated carbon carrying the smaller number of hydrogen atoms Originally this was an empirical rule, but in the meantime quantuni chemistry and molecular orbital theory have provided a solid theoretical background to it. In the particular case of propylene, for instance, it has been calculated that the rr-electron density distribution is as follows ... 

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