Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5-6
pubmed:dateCreated
2004-1-22
pubmed:abstractText
Two new alkoxysilylated derivatives of (-)-(1R,2R)-1, 2-diaminocyclohexane: M = N-[(triethoxysilyl)propyl]-(-)-(1R,2R)-1, 2-diaminocyclohexane and B = N, N'-bis[(triethoxysilyl)propyl]-(-)-(1R,2R)-1,2-diaminocyclohexane have been synthesized. Their complexation with [Rh(cod)Cl]2 in the presence of TEOS = Si(OEt)4, followed by sol-gel hydrolysis-condensation, afforded new catalytic chiral hybrid materials. Evidence for the presence of the organic moieties complexed by rhodium in these solids was obtained by UV-visible spectroscopy, FT-IR studies, solid state 13C and 29Si CP-MAS NMR analysis, energy-dispersive X-ray (EDX) techniques, and elemental analysis. The nitrogen sorption studies and BET analyses ranged these solid gels from nonporous to highly porous materials. The catalytic activities and selectivities of the solid materials have been studied in the asymmetric hydrogen-transfer reduction of prochiral ketones and compared to that of the homogeneous rhodium complexes of the ligands M and B. The hybrid materials appeared interesting supports for enantioselective heterogeneous catalysis leading to chiral alcohols with ee up to 58% in the reduction of acetophenone and up to 98% in the case of the more hindered related ketones. The catalytic properties as a function of the nature of chiral hybrid solid are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0899-0042
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
411-20
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Immobilization of rhodium complexes in chiral organic-inorganic hybrid materials.
pubmed:affiliation
Laboratoire de Chimie Organometallique, Ecole Nationale Superieure de Chimie de Montpellier, Montpellier, France.
pubmed:publicationType
Journal Article