Abstract
A tandem three-step, one-pot method for the conversion of aldehydes into β-substituted-2-oxohex-5-enoic acids 1 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.
Key words
tandem reactions - rearrangements - domino reactions - Wittig reactions - carboxylic acids
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