851348-19-1Relevant academic research and scientific papers
Diastereoselective Method of Preparing Olefins by Means of the Horner-Wadsworth-Emmons Reaction Using a Particular Phosphonate Which Improves Diastereoselectivity at all Temperatures Including at Ambient Temperature
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Page/Page column 4, (2010/11/29)
The invention relates to a diastereoselective process for the preparation of olefins by the Horner-Wadsworth-Emmons reaction which consists in reacting a specific phosphonate improve the diastereoselectivity at all temperatures including at ambient temperature, with a carbonyl derivative in the presence of a base in an appropriate solvent.
Phosphonate modification for a highly (Z)-selective synthesis of unsaturated esters by Horner-Wadsworth-Emmons olefination
Touchard, Francois P.
, p. 1790 - 1794 (2007/10/03)
The Horner-Wadsworth-Emmons (HWE) reaction of various ethyl diarylphosphonoacetates with benzaldehyde, cyclohexane carboxaldehyde and octanal is reported. Selectivities of up to 98% at -78°C are obtained with the three substrates. Among all the phosphonates prepared, the reagent based on 2-tert-butylphenol proved to be especially efficient, with Z/E ratios close to 95:5 at 0°C. It appears thus to be the reagent of choice for the (Z)-selective HWE reaction with both aromatic and aliphatic aldehydes. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
