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The Kharasch–Sosnovsky reaction is a method that involves using a copper or cobalt salt as a catalyst to oxidize olefins at the allylic position, subsequently condensing a peroxy ester (e.g. tert-Butyl peroxybenzoate) or a peroxide resulting in the formation of allylic benzoates or alcohols via radical oxidation. [1]
Jacobsen's catalysts R = Alkyl, O-alkyl, O-trialkyl Best Jacobsen catalyst: R = t Bu Katsuki's catalysts R 1 = Aryl, substituted aryl R 2 = Aryl, Alkyl. The Jacobsen epoxidation, sometimes also referred to as Jacobsen-Katsuki epoxidation is a chemical reaction which allows enantioselective epoxidation of unfunctionalized alkyl- and aryl- substituted alkenes.
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 ...
A remarkable feature of these reactions is the ability to conduct carbonyl allylation from the alcohol oxidation state. Due to a kinetic preference for primary alcohol dehydrogenation, diols containing both primary and secondary alcohols undergo site-selective carbonyl allylation at the primary alcohol without the need for protecting groups ...
The first example of an enantioselective Rubottom oxidation was published by F.A. Davis [21] in 1987 and showcased the Davis chiral oxaziridine methodology ...
There have been several enantioselective versions of this reaction developed, and even employed in synthesis of complex molecules. Hoyveda's synthesis of ( R )-(-)-sporochnol included an asymmetric copper-catalyzed allylic substitution with an organozinc nucleophile and peptide ligand.
This observation is attributed to a balance of two factors. The first is the stabilization of the transition state as a result of the hydrogen bonding. 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 ...
The Tsuji–Trost reaction (also called the Trost allylic alkylation or allylic alkylation) is a palladium-catalysed substitution reaction involving a substrate that contains a leaving group in an allylic position. The palladium catalyst first coordinates with the allyl group and then undergoes oxidative addition, forming the π-allyl complex.