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Allyl alcohol is converted mainly to glycidol, which is a chemical intermediate in the synthesis of glycerol, glycidyl ethers, esters, and amines. Also, a variety of polymerizable esters are prepared from allyl alcohol, e.g. diallyl phthalate. [5] Allyl alcohol has herbicidal activity and can be used as a weed eradicant [9]) and fungicide. [8]
The Wharton olefin synthesis allows the transformation of an α,β unsaturated ketone into an allylic alcohol. The epoxide starting material can be generated by a number of methods, with the most common being reaction of the corresponding alkene with hydrogen peroxide or m-chloroperoxybenzoic acid. The Wharton reaction also commonly suffers ...
An allylic rearrangement or allylic shift is an organic chemical reaction in which reaction at a center vicinal to a double bond causes the double bond to shift to an adjacent pair of atoms: It is encountered in both nucleophilic and electrophilic substitution , although it is usually suppressed relative to non-allylic substitution.
If Y is sulfur, the product can be treated with a thiophil to generate an allylic alcohol in what is known as the Mislow–Evans rearrangement. A [2,3]-rearrangement may result in carbon-carbon bond formation. It can also be used as a ring-expansion reaction. [2]
A site adjacent to the unsaturated carbon atom is called the allylic position or allylic site. A group attached at this site is sometimes described as allylic. Thus, CH 2 =CHCH 2 OH "has an allylic hydroxyl group". Allylic C−H bonds are about 15% weaker than the C−H bonds in ordinary sp 3 carbon centers and are thus more reactive.
The mechanism starts with an allylic sulfoxide 1 which undergoes a thermal 2,3-sigmatropic rearrangement to give a sulfenate ester 2. This can be cleaved using a thiophile, such as phosphite ester , which leaves the allylic alcohol 3 as the product.
Carbonyl allylation has been employed in the synthesis of polyketide natural products and other oxygenated molecules with a contiguous array of stereocenters. For example, allylstannanation of a threose-derived aldehyde affords the macrolide antascomicin B, which structurally resembles FK506 and rapamycin, and is a potent binder of FKBP12. [12]
Chavicol is formed in sweet basil (Ocimum Basilicum) by the phenylpropanoid pathway via p-coumaryl alcohol. The allylic alcohol in p -coumaryl alcohol is converted into a leaving group. This then leaves thus forming a cation, this cation can be regarded as a quinone methide which then is reduced by NADPH to form either anol or chavicol.