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In organic chemistry, olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. [ 1 ] [ 2 ] Because of the relative simplicity of olefin metathesis, it often creates fewer undesired by-products and hazardous wastes than alternative ...
The metal-mediated processes include a carbonyl-olefination and an olefin–olefin metathesis event. There are two general mechanistic schemes to perform this overall transformation: one, reaction of a [M=CHR 1] reagent with an alkene to generate a new metal alkylidene, which then couples with a carbonyl group to form the desired substituted alkene and an inactive [M=O] species (type A); two ...
Grubbs catalysts are of interest for olefin metathesis. [ 25 ] [ 26 ] It is mainly applied to fine chemical synthesis. Large-scale commercial applications of olefin metathesis almost always employ heterogeneous catalysts or ill-defined systems based on ruthenium trichloride.
Grubbs was instrumental in developing a family of ruthenium catalysts, including Grubbs catalyst for olefin metathesis. [36] He studied olefin transformations for ring-closing metathesis (RCM), [37] cross-metathesis reaction (CMR), [38] and ring-opening metathesis polymerization (ROMP) with cyclic olefins such as norbornene. [39]
The Shell higher olefin process (SHOP) is a chemical process for the production of linear alpha olefins via ethylene oligomerization and olefin metathesis invented and exploited by Shell plc. [1] The olefin products are converted to fatty aldehydes and then to fatty alcohols , which are precursors to plasticizers and detergents .
The mechanism of homogeneous ring-opening metathesis polymerization is well-studied. It is similar to any olefin metathesis reaction. Initiation occurs by forming an open coordination site on the catalyst. Propagation happens via a metallacycle intermediate formed after a 2+2 cycloaddition. When using a G3 catalyst, 2+2 cycloaddition is the ...
The reaction is an example of cross metathesis. The utility of the reaction is driven by the low cost of ethylene as a reagent and its selectivity. It produces compounds with terminal alkene functional groups (α-olefins), which are more amenable to other reactions such as polymerization and hydroformylation. The general reaction equation is:
Ring-closing metathesis (RCM) is a widely used variation of olefin metathesis in organic chemistry for the synthesis of various unsaturated rings via the intramolecular metathesis of two terminal alkenes, which forms the cycloalkene as the E-or Z-isomers and volatile ethylene.