228271-59-8Relevant articles and documents
Stereochemistry of 3-oxo-5-phenylcyclo-pentanecarboxylic acids, XI: Syntheses of stereomeric 3-oxo-5-pyridylcyclopentanecarboxylic acids
Beck,Frahm
, p. 366 - 372 (1986)
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Diastereoselective method of preparing olefins by means of the horner-wadsworthemmons reaction, comprising the addition of a tris-(polyoxaalkyl)-amine sequestering agent
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Page/Page column 5-6, (2010/11/08)
The invention relates to a process for the diastereoselective preparation of olefins via the Homer-Wadsworth-Emmons reaction, which consists in reacting at low temperature a phosphonate with a carbonyl derivative in the presence of a base in a suitable solvent, characterized in that a tris(polyoxaalkyl)amine sequestering reagent of formula (I): N—[CHR1—CHR2—O—(CHR3—CHR4—O)n—R5]3 (I), wherein: n is an integer between 0 and 10; R1, R2, R3 and R4 may be identical or different, and represent a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms; R5 represents a hydrogen atom, an alkyl or cycloalkyl radical containing up to 12 carbon atoms, a phenyl radical or a radical of formula —CμH2μ-Φ, or CmH2m+1-Φ-, with m being an integer between 1 and 12 and Φ being a phenyl radical; is added in an amount that is sufficient to increase the diastereoselectivity of the olefin.