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DOI: 10.1055/s-2005-918452
Tandem Horner-Wadsworth-Emmons Olefination/Claisen Rearrangement/Hydrolysis Sequence: Remarkable Acceleration in Water with Microwave Irradiation
Publication History
Publication Date:
27 October 2005 (online)
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
- 1x Present address: Instituto de Quimica Medica CSIC, Juan de la Cierva 3, 28006 Madrid, Spain. E-mail: EQ1@iqm.csic.es
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References
Crystallographic data for 1a can be obtained on request from The Director, Cambridge Crystallographic Data Centre, University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW, UK. CCDC reference number: 255362. Selected crystallographic data: C12H12O3·C12H12O3 (dimer), M = 408.44, crystal system: Monoclinic, a = 16.103 (4), b = 5.4841 (12), c = 23.444 (5) Å, U = 2058.3 (8) Å3, T = 115 (2) K, space group P2 (1)/c, Z = 8, µ = 0.094 mm-1, 11027 reflections measured.