摘要:
Osmium-catalyzed methods of addition to an olefin are discussed. In the method of asymmetric dihydroxylation of the present invention, an olefin, a chiral ligand, an organic solvent, an aqueous solution, a base, a ferricyanide salt and an osmium-containing compound are combined. The chiral ligand is an alkaloid or alkaloid derivative linked to an organic substituent of at least 300 daltons molecular weight through a planar aromatic spacer group. The organic substituent can be another alkaloid or alkaloid derivative. With the described chiral ligands, asymmetric dihydroxylation of olefins with high yields and enantiomeric excesses are achieved.
摘要:
Manganese(IV) complex salts of formula [LMn(mu-O) 3 MnL] n [XM 12 O 40 ] m , (I), wherein L is 1,4,7-trimethyl-1,4,7-triazacyclononane, X is P or Si, M is Mo or W, n is 2 or 3, and m is 1 or 2, with the provisos that (i) if X is Si, then n=2 and m=1 and (ii) if X is P, then n=3 and m=2. These compounds are active catalysts in the partial oxidation of various organic compounds with peroxy compounds, e.g., the preparation of ketones from secondary alcohols or the epoxidation of olefins.
摘要:
Osmium-catalyzed methods of addition to an olefin are discussed. In the method of asymmetric dihydroxylation of the present invention, an olefin, a chiral ligand, an organic solvent, water, an oxidant 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, a metallochloramine derivative, an osmium-containing compound and, optionally, a tetraalkyl ammonium 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, an amine and an osmium-containing compound are combined. In one embodiment, an olefin, a chiral ligand which is a polymeric dihydroquinidine derivative or a dihydroquinine derivative, acetone, water, a base, an oxidant and osmium tetroxide are combined to effect asymmetric dihydroxylation of the olefin.