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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
Publikationsverlauf
Publikationsdatum:
27. Oktober 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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1a
Raw SA.Taylor RJK. J. Am. Chem. Soc. 2004, 126: 12260 -
1b
Oswald MF.Raw SA.Taylor RJK. Org. Lett. 2004, 6: 3997 ; and references cited therein -
1c
Taylor RJK.Reid M.Foot J.Raw SA. Acc. Chem. Res. in press - For recent reviews see:
-
2a
Martín Castro AM. Chem. Rev. 2004, 104: 2939 -
2b
Ito H.Taguchi T. Chem. Soc. Rev. 1999, 28: 43 -
3a
Kulkarni MG.Pendharkar DS.Rasne RM. Tetrahedron Lett. 1997, 38: 1459 -
3b For olefination thio-Claisen rearrangement see:
Corey EJ.Shulman JI. J. Am. Chem. Soc. 1970, 92: 5522 -
4a
Schobert R.Gordon GJ. Curr. Org. Chem. 2002, 6: 1181 -
4b
Loffler J.Schobert R. J. Chem. Soc., Perkin Trans. 1 1996, 2799 - 5
Schobert R.Gordon GJ.Mullen G.Stehle R. Tetrahedron Lett. 2004, 45: 1121 - 6
Tanako S.Tomita S.Takahashi M.Ogasawara K. Synthesis 1987, 1116 - 7
Ye T.McKervey MA. Chem. Rev. 1994, 94: 1091 - 8
Villieras J.Rambaud M. Synthesis 1983, 300 - 10
Gajewski JJ. Acc. Chem. Res. 1997, 30: 219
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.