β-Hydride elimination

β-Hydride elimination is a reaction in which a metal-<a href="/facts/Alkyl/vmEk8X4v">alkyl</a> centre is converted into the corresponding metal-<a href="/facts/Hydride/v2rlBGMg">hydride</a>-<a href="/facts/Alkene/RtYcS6kU">alkene</a>. β-Hydride elimination can also occur for many alkoxide complexes as well. The main requirements are that the alkyl group possess a C-H bond β to the metal and that the metal be coordinatively unsaturated. Thus, metal-<a href="/facts/Butyl/fbTF0UkI">butyl</a> complexes are susceptible to this reaction whereas metal-<a href="/facts/Methyl/fkM97EMD">methyl</a> complexes are not. The complex must have an empty (or vacant) site <a href="/facts/Cis_isomer/vqlchJly">cis</a> to the <a href="/facts/Alkyl/vmEk8X4v">alkyl</a> group for this reaction to occur. β-Hydride elimination, which can be desirable or undesirable, affects the behavior of many <a href="/facts/Organometallic_complex/bhqFz2P0">organometallic complexes</a>. 
Moreover, for facile cleavage of the C–H bond, a d electron pair is needed for donation into the σ* orbital of the C–H bond. Thus, d0 metals alkyls are generally more stable to β-hydride elimination than d2 and higher metal alkyls and may form isolable <a href="/facts/Agostic_interaction/4VDvImoz">agostic complexes</a>, even if an empty coordination site is available.

β-Hydride elimination open-in-new

β-Hydride elimination