Oxazaborolidine-catalysed reduction of alk-2-ene-1,4-diones. A convenient access to chiral 1,4-diols
An efficient method for the preparation of C 2-symmetric, chiral alk-2-ene-1,4-diols ( 4) has been achieved, based on the borane-mediated reduction of symmetric alk-2-ene-1,4-diones ( 2) in the presence of oxazaborolidine (R)- 1 . In general, the presence of the double bond in 2 has been beneficial...
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Published in | Tetrahedron Vol. 54; no. 49; pp. 14947 - 14962 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Elsevier Ltd
03.12.1998
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Subjects | |
Online Access | Get full text |
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Summary: | An efficient method for the preparation of
C
2-symmetric, chiral alk-2-ene-1,4-diols (
4) has been achieved, based on the borane-mediated reduction of symmetric alk-2-ene-1,4-diones (
2) in the presence of oxazaborolidine
(R)-
1
. In general, the presence of the double bond in
2 has been beneficial (compared with the related saturated 1,4-diketones
3) not only as far as the stereoselectivity in the reduction step is concerned, but also because it allowed us to remove
meso-
4 by chomatography and/or to improve the stereochemical purity of several resulting mixtures of diols
4 by Sharpless' epoxidation. Enantioenriched compounds
4 have been readily reduced to saturated diols with negligible loss of optical purity.
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ISSN: | 0040-4020 1464-5416 |
DOI: | 10.1016/S0040-4020(98)00936-3 |