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An illustrative example is the epoxidation of trans-2-butene with m-CPBA to give trans-2,3-epoxybutane: [4] The oxygen atom that adds across the double bond of the alkene is taken from the peroxy acid, generating a molecule of the corresponding carboxylic acid as a byproduct.
meta-Chloroperoxybenzoic acid (mCPBA or mCPBA) is a peroxycarboxylic acid. It is a white solid often used widely as an oxidant in organic synthesis. mCPBA is often preferred to other peroxy acids because of its relative ease of handling. [1] mCPBA is a strong oxidizing agent that may cause fire upon contact with flammable material. [2]
The second is the electron-withdrawing nature of the oxygen, which draws electron density away from the alkene, lowering its reactivity. [5] Acyclic allylic alcohols exhibit good selectivity as well. In these systems both A 1,2 (steric interactions with vinyl) and A 1,3 strain are considered.
Although many different peroxyacids are used for the Baeyer–Villiger oxidation, some of the more common oxidants include meta-chloroperbenzoic acid (mCPBA) and trifluoroperacetic acid (TFPAA). [2] The general trend is that higher reactivity is correlated with lower pK a (i.e.: stronger acidity) of the corresponding carboxylic acid (or alcohol ...
The Sharpless epoxidation is viable with a large range of primary and secondary alkenic alcohols. Furthermore, with the exception noted above, a given dialkyl tartrate will preferentially add to the same face independent of the substitution on the alkene.To demonstrate the synthetic utility of the Sharpless epoxidation, the Sharpless group created synthetic intermediates of various natural ...
The radicals formed from alkenyl peroxides can be utilized in organic radical reactions. For example, they can mediate hydrogen atom abstraction reactions and thus lead to the functionalization of C-H bonds, [7] or they can be used to introduce ketone residues by addition of the alkenyloxyl radicals to alkenes. [8] [9] [10]
In the example shown below, the para-methoxybenzoyl substituent serves primarily as a source of steric bulk to allow the catalyst to differentiate the two faces of the alkene. [23] SAD scheme 3. It is often difficult to obtain high diastereoselectivity on cis-disubstituted alkenes when both ends of the olefin have similar steric environments.
Imine are oxidized with meta-chloroperoxybenzoic acid (mCPBA) to give an oxaziridines. Imines are intermediates in the alkylation of amines with formic acid in the Eschweiler-Clarke reaction . A rearrangement in carbohydrate chemistry involving an imine is the Amadori rearrangement .