The Wittig reaction is a chemical reaction of an aldehyde or ketone with a phosphonium ylide to give an alkene and triphenylphosphine oxide. This article is in need of attention. ... kjhfckjdsvsdv ... A ketone is either the functional group characterized by a carbonyl group linked to two other carbon atoms or a compound that contains this functional group. ... An alkene is one of the three classes of unsaturated hydrocarbons that contain at least one carbon- carbon double bond and have the general molecular formula of CnH2n (the other two being alkynes and arenes). ...
This reaction was discovered in 1954 by Georg Wittig, for which he was awarded the Nobel Prize in Chemistry in 1979. Wikipedia does not have an article with this exact name. ... 1954 was a common year starting on Friday (link will take you to calendar). ... Georg Wittig (June 16, 1897 in Berlin (Germany) - August 26, 1987) was a german chemist who reported a method for synthesis of alkenes from aldehydes and ketones using compounds called phosphonium ylides. ... List of Nobel Prize laureates in Chemistry from 1901 to the present day. ... 1979 is a common year starting on Monday. ...
Wittig reactions are most commonly used to couple aldehydes to singly substituted phosphine ylides. This results in almost exclusively the Z-alkene product. In order to obtain the E-alkene, the Schlosser modification of the Wittig reaction can be performed.
A principal advantage of alkene synthesis by the Wittigreaction is that the location of the double bond is absolutely fixed, in contrast to the mixtures often produced by alcohol dehydration.
Grignard reactions may be shifted to a 1,4-addition mode by adding copper salts, but a better strategy is to use a Gilman reagent, as shown in the last two equations.
The use of phosphorous ylides in the Wittigreaction is an example of this reactivity.
The Wittigreaction was discovered in 1954 by Georg Wittig, for which he was awarded the Nobel Prize in Chemistry in 1979.
The Wittig reagent is usually prepared from a phosphonium salt, which is in turn made by the reaction of triphenylphosphine with an alkyl halide.
To form the Wittig reagent (ylide), the phosphonium salt is suspended in a solvent such as diethyl ether or THF and a strong base such as phenyllithium or n-butyllithium is added.
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