373392-28-0Relevant articles and documents
Nickel-Catalyzed Cyanation of Benzylic and Allylic Pivalate Esters
Michel, Nicholas W. M.,Jeanneret, Alexandria D. M.,Kim, Hyehwang,Rousseaux, Sophie A. L.
, p. 11860 - 11872 (2018)
A nickel-catalyzed cyanation reaction of benzylic and allylic pivalate esters is reported using an air-stable Ni(II) precatalyst and substoichiometric quantities of Zn(CN)2. Alkene additives were found to inhibit catalysis, suggesting that avoiding β-hydride elimination side reactions is essential for productive catalysis. An enantioenriched allylic ester undergoes enantiospecific cross-coupling to produce an enantioenriched allylic nitrile. This method was applied to an efficient synthesis of (±)-naproxen from commercially available starting materials.
A convenient and versatile method for the preparation of α-hydroxymethyl ketone derivatives from the corresponding allyl silyl ethers or allyl carboxylates
Hon, Yung-Son,Wong, Ying-Chieh,Wu, Kuo-Jui
experimental part, p. 896 - 914 (2009/12/06)
The ozonolysis of 1-substituted allyl silyl ethers or 1-substituted allyl carboxylates followed by treatment with bases gave the corresponding α-silyloxymethyl- or α-acyloxymethyl-ketones in good yields. It is proposed to proceed via the corresponding α-silyloxy- or α-acyloxyaldehydes intermediates followed by 1,4-group migration. The results of theoretical calculations are applicable to explain the experimental results.
Enantioconvergent synthesis by sequential asymmetric Horner-Wadsworth-Emmons and palladium-catalyzed allylic substitution reactions
Pedersen,Hansen,Kane,Rein,Helquist,Norrby,Tanner
, p. 9738 - 9742 (2007/10/03)
A new method for enantioconvergent synthesis has been developed. The strategy relies on the combination of an asymmetric Horner-Wadsworth-Emmons (HWE) reaction and a palladium-catalyzed allylic substitution. Different α-oxygen-substituted, racemic aldehydes were initially transformed by asymmetric HWE reactions into mixtures of two major α,β-unsaturated esters, possessing opposite configurations at their allylic stereocenters as well as opposite alkene geometry. Subsequently, these isomeric mixtures of alkenes could be subjected to palladium-catalyzed allylic substitution reactions with carbon, nitrogen, and oxygen nucleophiles. In this latter step, the respective (E) and (Z) alkene substrate isomers were observed to react with opposite stereospecificity: the (E) alkene reacted with retention and the (Z) alkene with inversion of stereochemistry with respect to both the allylic stereocenter and the alkene geometry. Thus, a single γ-substituted ester was obtained as the overall product, in high isomeric purity. The method was applied to a synthesis of a subunit of the iejimalides, a group of cytotoxic macrolides.
