Tandem Horner-Wadsworth-Emmons Olefination/Claisen Rearrangement/Hydrolysis Sequence: Remarkable Acceleration in Water with Microwave Irradiation
Ernesto Quesada, Richard J. K. Taylor*
*Department of Chemistry, University of York, Heslington, York YO10 5DD, UK, Email: rjkt1york.ac.uk
E. Quesada, R. J. K. Taylor, Synthesis, 2005, 3193-3195.
A tandem three-step, one-pot method for the conversion of aldehydes into β-substituted-2-oxohex-5-enoic acids in good to excellent yield is described. The optimised sequence is carried out in water with microwave irradiation and involves sequential Horner-Wadsworth-Emmons (HWE) olefination, Claisen rearrangement and ester hydrolysis. The outcome of this domino sequence can be controlled by the temperature of the process.
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