Carbenoids
In chemistry, a carbenoid is a reactive intermediate that has the characteristic property of a carbene or serves as a source of carbenes. They are produced in situ from geminal dihalogen compounds by transmetallation z. B. with organic lithium compounds or by metalation by reaction with the elemental metals.
Carbenoids occur as reactive intermediates in a number of reactions. This includes, for example, the Simmons-Smith reaction . The carbenoid is obtained by reacting diiodomethane with a zinc-copper pair . This then reacts with an alkene to form a cyclopropane; actually a typical reaction of a carbene.
Another example of a reaction of carbenoids is the Fritsch-Buttenberg-Wiechell rearrangement . The carbenoid is obtained by lithiation of a geminal vinyl dihalide with butyllithium. This is then rearranged to the substituted acetylene (alkyne).
literature
- Jerry March: Advanced Organic Chemistry, John Wiley & Sons, New York 1985, ISBN 0-471-88841-9 .
Individual evidence
- ^ Organic Chemistry , John McMurry Brooks, Cole Publishing Company, 1988, ISBN 0-534-07968-7 .
- ↑ Entry on carbenoids . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.C00813 Version: 2.3 ..