A method of selective conversion of Abienol, represented by formula 1, to Sclareodiol, represented by formula 2

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by ozonolysis and subsequent reduction. The ozonolysis is carried out at temperatures above 60 C., preferably in nonhalogenated solvents. R is selected from H, acetals, aminals, optionally substituted alkyl groups, such as benzyl group, carboxylates such as acetates or formates, carbonates such as methyl or ethyl carbonates, carbamates, and any protecting group which can be attached to 1 and cleaved from 2, R is selected from CHCH.sub.2, an alkyl moiety with C2-C20, e.g. CH.sub.2CH.sub.3, or a cycloalkyl or polycycloalkyl moiety with C3-C20, e.g. cyclopropyl, optionally alkylated, respectively, and the wavy bond is depicting an unspecified configuration of the adjacent double bond between C2 and C3.

A process for the hydrogenation of a substrate comprising a carbon heteroatom double bond in the presence of a transition metal complex comprising a tridentate or bisdentate-ligand containing a nitrogen, sulphur and phosphorus atom, of which at least the N- and P- and optionally also the S-atom coordinates with the transition metal.

A process for the hydrogenation of a substrate comprising a carbon heteroatom double bond in the presence of a transition metal complex comprising a tridentate or bisdentate-ligand containing a nitrogen, sulphur and phosphorus atom, of which at least the N- and P- and optionally also the S-atom coordinates with the transition metal.

A process for the hydrogenation of a substrate comprising a carbon heteroatom double bond in the presence of a transition metal complex comprising a tridentate or bisdentate-ligand containing a nitrogen, sulphur and phosphorus atom, of which at least the N- and P- and optionally also the S-atom coordinates with the transition metal.

A process for the stereoselective preparation of a chiral alcohol or a chiral amine, the process comprising reacting a first prochiral reactant selected from the group consisting of a ketone, an aldehyde, and an imine, with a second reactant comprising a Grignard reagent, in the presence of a chiral trans-diamine of formula (1) as defined herein:

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Also provided is the use of the chiral trans-diamine of formula (1) in a Grignard reaction and the chiral trans-diamines per se.

A process for the stereoselective preparation of a chiral alcohol or a chiral amine, the process comprising reacting a first prochiral reactant selected from the group consisting of a ketone, an aldehyde, and an imine, with a second reactant comprising a Grignard reagent, in the presence of a chiral trans-diamine of formula (1) as defined herein:

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Also provided is the use of the chiral trans-diamine of formula (1) in a Grignard reaction and the chiral trans-diamines per se.

The conversion of nootkatol to nootkatene in a terpene blend is mitigated or prevented by substantially or completely separating the nootkatols such as -nootkatol from compounds present in the terpene blend that catalyze the chemical reaction of nootkatol to nootkatene, and/or by at least partially neutralizing the compounds present in the terpene blend that catalyze the chemical reaction of nootkatol to nootkatene. Methods of preparing terpene blends, terpene blends, flavour compositions containing the terpene blends, beverages and foodstuffs containing the flavour compositions, fragrance compositions containing the terpene blends, and fragranced products containing the fragrance composition are also disclosed.

The conversion of nootkatol to nootkatene in a terpene blend is mitigated or prevented by substantially or completely separating the nootkatols such as -nootkatol from compounds present in the terpene blend that catalyze the chemical reaction of nootkatol to nootkatene, and/or by at least partially neutralizing the compounds present in the terpene blend that catalyze the chemical reaction of nootkatol to nootkatene. Methods of preparing terpene blends, terpene blends, flavour compositions containing the terpene blends, beverages and foodstuffs containing the flavour compositions, fragrance compositions containing the terpene blends, and fragranced products containing the fragrance composition are also disclosed.