Daniel J Dobbs

US Patent:

6455460, Sep 24, 2002

Filed:

Oct 18, 2000

Appl. No.:

09/690980

Inventors:

Daniel A. Dobbs - Metuchen NJ
Koenraad P. M. Vanhessche - Basking Ridge NJ
Valentin Rautenstrauch - Bernex, CH

Assignee:

Firmenich SA - Geneva

International Classification:

B01J 3100

US Classification:

502155, 502162

Abstract:

A catalyst of ruthenium (II) comprising bidentate phosphine ligands is described which is obtained by a process that comprises treating equimolar amounts of an appropriate Ru complex and a bidentate diphosphine ligand with an acid of the formula H-Anion, wherein the anion is a non-coordinating anion, said acid being used in a ratio of 1 molar equivalent per mole of Ru complex and the treatment being carried out in a non-coordinating or weakly coordinating medium, under an oxygen-free atmosphere. Said catalyst is useful for the preparation of the preferred isomer of the HedioneÂ, having the configuration (+)-(1R)-cis, and of many other substrates comprising highly hindered carbon-carbon double bonds.

US Patent:

62147633, Apr 10, 2001

Filed:

May 19, 1998

Appl. No.:

9/081013

Inventors:

Daniel A. Dobbs - Metuchen NJ
Koenraad P. M. Vanhessche - Basking Ridge NJ
Valentin Rautens Trauch - Bernex, CH

Assignee:

Firmenich SA - Geneva

International Classification:

B01J 3100
C07C 502
C07C 503

US Classification:

502155

Abstract:

A catalyst of Ru comprising bidentate phosphine ligands is described which is obtained by a process that comprises treating equimolar amounts of an appropriate Ru complex and a bidentate diphosphine ligand with an acid of the formula H-Anion, wherein the anion is a non-coordinating anion, said acid being used in a ratio of 1 molar equivalent per mole of Ru complex and the treatment being carried out in a non-coordinating or weakly coordinating medium, under an oxygen-free atmosphere. Said catalyst is useful for the preparation of the preferred isomer of the Hedione. RTM. , having the configuration (+)-(1R)-cis, and of many other substrates comprising highly hindered carbon-carbon double bonds.