Abstract
(+)-Dicarbonyl-μ-chloro[μ-(2-methyl-2-propanethiolato-S:S)]bis{[5-methyl-2-(1-methylethyl)cyclohexyl] diphenylphosphine}dirhodium (6a) and (+) - dicarbonyl-μ-chloro[μ-(2-triethoxysilyl)ethanethiolato-S:S]bis{[5-methyl-2-(1-methylethyl)cyclohexyl] diphenylphosphine}dirhodium (6b) were prepared by interaction of (+)-neomenthyldiphenylphosphine (3) with chlorodicarbonylrhodium dimer (2), followed by treatment of the product with the appropriate (alkylthio)trimethylsilane, 5. Complex 6b was immobilized by attachment to silica gel. Both the homogeneous and hybrid catalyts proved capable of promoting the asymmetric hydrogenation of prochiral unsaturated acids and esters. While the soluble complexes 6a and 6b led to the formation of dextro-rotatory products, the recyclable supported catalyst gave laevorotatory compounds.
Original language | English |
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Pages (from-to) | 329-337 |
Number of pages | 9 |
Journal | Journal of Molecular Catalysis |
Volume | 56 |
Issue number | 1-3 |
DOIs | |
State | Published - 15 Nov 1989 |
Externally published | Yes |