Patent
Ligand-accelerated catalytic asymmetric dihydroxylation using dihydroquinidine and dihydroquinidine esters as ligands
TLDR
In this paper, an osmium-catalyzed method of addition to an olefin was presented, where a chiral ligand, an organic solvent, water, and an amine derivative were combined.Abstract:
An osmium-catalyzed method of addition to an olefin. In the method of asymmetric dihydroxylation of the present invention, an olefin, a chiral ligand, an organic solvent, water, and aamine oxide and an osmium-containing compound are combined. In the method of asymmetric oxyamination of the present invention, an olefin, a chiral ligand, an organic solvent, water, an amine derivative and an osmium-containing compound are combined. In the method of asymmetric diamination of the present invention, an olefin, a chiral ligand, an organic solvent, a metallo-chloramine derivative or an amine derivative and an osmium-containing compound are combined. In one embodiment, an olefin, a chiral ligand which is a dihydroquinidine derivative or a dihydroquinine derivative, acetone, water, N-methyl morpholine N-oxide and osmium tetroxide are combined to effect asymmetric dihydroxylation of the olefin.read more
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Patent
Ligands for ADH: cinchona alkaloids and moderately sized organic substituents linked through a planar aromatic spacer group
Jens Hartung,K. Barry Sharpless +1 more
TL;DR: In this article, an olefin, a chiral ligand, an organic solvent, an aqueous solution, a base, a ferricyanide salt and an osmium-containing compound are combined.
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Process for the hydroxylation of olefins using molecular oxygen, an osmium containing catalyst, a copper Co-catalyst, and an aromatic amine based promoter
TL;DR: In this paper, a process directed to the hydroxylation of olefins by reacting them in the presence of oxygen, water, and a catalyst composition comprising (i) a catalytically active osmium containing compound, (ii) a co-catalyst I comprising a copper containing compound such as CuBr2, and (iii) a Co-cateralyst II capable of increasing the rate and/or selectivity of the reaction, such as pyridine is disclosed.
Related Papers (5)
Ligands for ADH: cinchona alkaloids and moderately sized organic substituents linked through a planar aromatic spacer group
Jens Hartung,K. Barry Sharpless +1 more