Abstract:
Catalysts of formula [Ru(L)m(L′)wXY] (II) wherein X and Y represent simultaneously or independently a hydrogen or halogen atom, a hydroxy group, or an alkoxy, carboxyl or other anionic radical, m is 1 or 2, w is 1 when m is 1 and w is 0 when m is 2, L is a phosphino-amine or phosphino-imine bidentate ligand and L′ a diphosphine, are useful for the hydrogenation of substrates having a carbon-hetero atom double bond.
Abstract:
The invention concerns a fatty alcohol obtainable by a method which consists in reducing the carbonyl function of a vegetable or animal oil, the method consisting in reacting said vegetable or animal oil with appropriate amounts of polymethylhydroxysiloxane (PMHS) in the presence of a catalytic system prepared from a metal salt or complex and a reduction agent, followed by hydrolysis of the resulting siloxane with a basic agent and separating and purifying the desired alcohol thus formed. Said alcohol can be used in a perfume composition, in particular as solubilizing agent.
Abstract:
A process for the enantioselective reduction of prochiral ketones to chiral alcohols by (a) the reaction of a prochiral ketone with a silane agent, which is present in a stoichiometric quantity, in the presence of a catalyst derived from a Zn, Co or Cd precursor compound and from a chiral amine, imine, alcohol or amino alcohol ligand; (b) the hydrolysis of the siloxane obtained using an appropriate agent; and (c) the separation and purification of the optically active alcohol formed. Polymethylhydrosiloxane (PMHS) is a preferred silane agent, zinc is a preferred metal, and the precursor compound is produced by reacting a salt or complex of the respective metal with the reducing agent. In another embodiment, an appropriate salt of the chosen metal is used directly in the reaction with the chiral ligand to produce the catalytic form after reaction with the ligand. The process enables high enantiomeric excesses (ee) to be obtained in chiral alcohols.
Abstract:
The present invention relates to a process for the preparation of alcohols by reduction of the carbonyl function in substrates belonging to the class of aldehydes, ketones, esters or lactones, which substrates may contain unsaturated functions other than carbonyl. This process includes the steps of reacting the carbonyl substrate with stoichiometric amounts of a silane in the presence of catalytic amounts of an active zinc compound which is monomeric and not a hydride, hydrolyzing the thus-obtained siloxane with a basic agent, and separating and purifying, if necessary, the thus-obtained alcohol. The catalytically active compound is generally obtained by the reaction of an oligomeric or polymeric precursor compound of zinc with a complexing agent.
Abstract:
Process for producing olefins from natural gas, the natural gas (2) is mainly fractionated (1) into methane (3) and higher hydrocarbons (4), the latter being then mainly fractionated (17, 20) into propane (9) and ethane (7). The methane (3), admixed with oxygen (6), passes through an oxidation reactor (5), receives the ethane (7) and the obtained mixture passes through a pyrolysis reactor (8). The effluent coming out of reactor (8) receives the propane (9) and the obtained mixture passes through a pyrolysis reactor (10). A hydrocarbon flow comprising olefins (12), more particularly ethylene and propene, is recovered.
Abstract:
Process for producing olefins from natural gas. The natural gas is fractionated (1). The methane (3) mixed with oxygen (6) crosses the oxidizing reactor (5), receives the C.sub.2 + hydrocarbons (7) and the mixture crosses the pyrolysis reactor (8). A hydrocarbons flow containing olefins (10) is collected.
Abstract:
Peroxidic complexes of vanadium, niobium or tantalum, wherein the metal is linked to an oxygen molecule carrying two negative charges, are used either as reactants for the oxidation of olefinic substrates or hydrocarbons, or as hydrocarbons oxidation catalysts, particularly for converting olefinic compounds to epoxides or aliphatic or aromatic hydrocarbons to the corresponding alcohols or phenols.
Abstract:
The present invention relates to a preparation of β-γ ene carboxylic or ketone derivatives, which may also have particular requirement on the configuration of the carbon-carbon double bond. The method requires a thermal treatment of α-β unsaturated malonate or acetylacetonate derivatives in the presents of at least one carboxylic acid and at least one alkaline, alkaline-earth or lanthanide halide or carboxylates.
Abstract:
The catalysts of formula (II): [Ru(L)m(L′)wXY], wherein X and Y represent simultaneously or independently a hydrogen or halogen atom, a hydroxy group, or an alkoxy, carboxyl or other anionic radical, m is 1 or 2, w is 1 when m is 1 and w is 0 when m is 2, L is a phosphino-amine or phosphino-imine bidentate ligand and L′ a diphosphine, are useful for the hydrogenation of substrates having a carbon-hetero atom double bond.
Abstract:
The catalysts of formula (II): [Ru(L)m(L′)wXY], wherein X and Y represent simultaneously or independently a hydrogen or halogen atom, a hydroxy group, or an alkoxy, carboxyl or other anionic radical, m is 1 or 2, w is 1 when m is 1 and w is 0 when m is 2, L is a phosphino-amine or phosphino-imine bidentate ligand and L′ a diphosphine, are useful for the hydrogenation of substrates having a carbon-hetero atom double bond.