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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 ...
In organic chemistry, ethenolysis is a chemical process in which internal olefins are degraded using ethylene (H 2 C=CH 2) as the reagent. 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.
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 ...
A commercially significant example is the production of vinyl chloride. The E2 mechanism provides a more reliable β-elimination method than E1 for most alkene syntheses. Most E2 eliminations start with an alkyl halide or alkyl sulfonate ester (such as a tosylate or triflate). When an alkyl halide is used, the reaction is called a ...
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 ...
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 .
Modern organic chemistry starts with the Wöhler synthesis in 1828. In the history of the Nobel Prize in Chemistry awards have been given for the invention of specific organic reactions such as the Grignard reaction in 1912, the Diels–Alder reaction in 1950, the Wittig reaction in 1979 and olefin metathesis in 2005.
Olefin metathesis is a formal exchange of the alkylidene fragments in two alkenes. It is a catalytic reaction with carbene , or more accurately, transition metal carbene complex intermediates. In this example ( ethenolysis , a pair of vinyl compounds form a new symmetrical alkene with expulsion of ethylene .