32829-97-3Relevant academic research and scientific papers
Lewis Base Activation of Silyl Acetals: Iridium-Catalyzed Reductive Horner-Wadsworth-Emmons Olefination
Dakarapu, Udaya Sree,Bokka, Apparao,Asgari, Parham,Trog, Gabriela,Hua, Yuanda,Nguyen, Hiep H.,Rahman, Nawal,Jeon, Junha
supporting information, p. 5792 - 5795 (2015/12/11)
A Lewis base promoted deprotonative pronucleophile addition to silyl acetals has been developed and applied to the iridium-catalyzed reductive Horner-Wadsworth-Emmons (HWE) olefination of esters and the chemoselective reduction of the resulting enoates. Lewis base activation of silyl acetals generates putative pentacoordinate silicate acetals, which fragment into aldehydes, silanes, and alkoxides in situ. Subsequent deprotonative metalation of phosphonate esters followed by HWE with aldehydes furnishes enoates. This operationally convenient, mechanistically unique protocol converts the traditionally challenging aryl, alkenyl, and alkynyl esters to homologated enoates at room temperature within a single vessel.
Pentacarbonylmanganese enolate and dienolate complexes. Preparative and mechanistic considerations
Masters, Andrew P.,Sorensen, Ted S.
, p. 492 - 501 (2007/10/02)
Reactions of pentacarbonyl manganate anion with 4-halocrotonate esters or 2-halocarboxylate esters result in a complex set of inorganic and organic products, usually including the expected dienolate (or enolate) complexes.The reaction variables include the counterion, solvent, and halo group.The mechanism of the reaction has been investigated by conducting a thorough characterization of the reaction products under various conditions and also by carrying out model reactions.One can rationalize most of the non-organometallic products using either a radical or carbanion mechanism, but the latter seems to fit the available data better.Experimental procedures for optimizing the yield of the organometallic dienolate or enolate complexes have been worked out.
