Olefination of Ketones Using a Gold(III)-Catalyzed Meyer−Schuster Rearrangement
作者:Douglas A. Engel、Gregory B. Dudley
DOI:10.1021/ol0616743
日期:2006.8.1
efficient olefination strategy for ketones is described. Ethoxyacetylide addition followed by a gold-catalyzed Meyer-Schuster rearrangement affords alpha,beta-unsaturated esters, generally in excellent overall yield from the starting ketones. The alkynophilicity of Au3+ promotes an interaction with the electron-rich acetylenes that catalyzes the Meyer-Schuster rearrangement selectively over other conceivable
Lewis acid-catalyzed Meyer–Schuster reactions: methodology for the olefination of aldehydes and ketones
作者:Douglas A. Engel、Susana S. Lopez、Gregory B. Dudley
DOI:10.1016/j.tet.2008.02.030
日期:2008.7
In principle, the most efficient and atom-economical means of converting an aldehyde or ketone into the homologated α,β-unsaturatedester is through addition/rearrangement sequences involving acetylenic π-bonds (Scheme 1). Implementation of such a strategy for the synthesis of α,β-unsaturatedesters is presented: addition of ethoxyacetylene followed by scandium(III) triflate-catalyzed Meyer–Schuster
Catalyst free synthesis of α-fluoro-β-hydroxy ketones/α-fluoro-ynols via electrophilic fluorination of tertiary propargyl alcohols using Selectfluor™ (F-TEDA-BF<sub>4</sub>)
作者:Naganaboina Naveen、Rengarajan Balamurugan
DOI:10.1039/c7ob00140a
日期:——
A facile method for the synthesis of α-fluoro-β-hydroxy ketones/α-fluoro-ynols from tertiary propargyl alcohols under electrophilic fluorination conditions using F-TEDA-BF4 has been presented. The products bear pharmaceutically important α-fluoroketone, gem-diaryl and fluorohydrin moieties in the same molecule. Interestingly, this catalyst free protocol results in monofluorination.
Synthesis of β-Substituted Chalcones from Phenones via Conjugated Nucleophilic Substitution of Propargylic Alcohols
作者:Daniel Chapdelaine、Taoufik Halima
DOI:10.1055/s-0031-1290677
日期:2012.7
Phenones can be efficiently transformed into beta-substituted chalcones in a two-step process. First, propargylic alcohols were obtained by addition of ethoxyacetylene anion to aromatic ketones. Activation of the propargylic alcohols using a catalytic amount of acid in the presence of an electron-rich aromatic ketone affords the title enones in moderate to good yields.