摘要:
The present invention relates to a process of hydrogenating an alkyne selectively to an alkene by hydrogen using a hydrogenation catalyst which is palladium supported on a carrier in the presence of an additive mixture of an organic phosphorus compound (AP) and an organic sulphur compound (AS).
摘要:
The present invention relates to a process of manufacturing (6R,10R)-6,10,14-trimetylpentadecan-2-one in a multistep synthesis from a mixture of E/Z isomers of (R)-6,10,14-trimetylpentadec-5-en-2-one. The process is very advantageous in that it forms in an efficient way the desired chiral product from a mixture of stereoisomers of the starting product.
摘要:
The present invention is directed to a process for the manufacture of 6,10-dimethylundecan-2-one comprising the step of hydrogenating (5Z)-nerylacetone with hydrogen in the presence of a catalyst, whereby the catalyst is capable of preferentially hydrogenating carbon-carbon double bonds over carbon-oxygen double bonds. Preferably the catalyst comprises a metal selected from the group consisting of palladium, platinum, rhodium, iridium and nickel and mixtures thereof. The 6,10-dimethylundecan-2-one obtained according to the process of the present invention may be used as starting material for isophytol and α-tocopherol (acetate) via 3,7,11-trimethyl-dodec-1-en-3-ol ("tetrahydronerolidol"; THNL), 6,10,14-trimethylpentadec-5-en-2-one ("(5E/5Z)-5,6-dehydro-C18-ketone") and 6,10,14-pentadecane-2-one ("C18-ketone") or alternatively via 3,7,11-trimethyl-dodec-1-yn-3-ol, 6,10,14-trimethylpentadec-4,5-dien-2-one ("C18-allene-ketone") and 6,10,14-pentadecane-2-one ("C18-ketone"). Thus, the present invention is also directed to such processes which comprise the step of hydrogenating (5Z)-nerylacetone according to the process of the present invention.
摘要:
The present invention is directed to a process for the manufacture of 6,10,14-trimethylpentadecan-2-one ("C18-ketone") comprising the step of hydrogenating a mixture of (3E,5E,9E)-3,4-dehydrofarnesylacetone and (3Z,5E,9E)-3,4-dehydrofarnesylacetone with hydrogen in the presence of a catalyst, whereby the catalyst is capable of preferentially hydrogenating carbon-carbon double bonds over carbon-oxygen double bonds. Preferably the catalyst comprises a metal selected from the group consisting of palladium, platinum, rhodium, iridium and nickel and mixtures thereof. A process for the preparation of (2E,6E)-farnesal by selective oxidation of (2E,6E)-farnesol and a process for the manufacture of a mixture of (3E,5E,9E)-3,4-dehydrofarnesylacetone and (3Z,5E,9E)-3,4-dehydrofarnesylacetone from (2E,6E)-farnesal is also disclosed.
摘要:
The present invention relates to a process of manufacturing compound having stereogenic centres from a mixture of E/Z isomers of unsaturated compounds having prochiral double bonds. The hydrogenation product has a specific desired configuration at the stereogenic centres. The process involves two asymmetric hydrogenation steps. The process is very advantageous in that it forms the desired chiral product from a mixture of stereoisomers of the starting product in an efficient way.
摘要:
The present invention relates to a process of manufacturing (6R,10R)-6,10,14-trimetylpentadecan-2-one in a multistep synthesis from (R)-3,7-dimethyloct-6-enal. The process is very advantageous in that it forms in an efficient way the desired chiral product from a mixture of stereoisomers of the starting product.
摘要:
The present invention relates to the photooxidation of phenolic compounds to the respective quinoid compounds using methylene blue as photosensitizer in a solvent mixture of water and alcohols using light of the high wavelength range of the visible spectrum.
摘要:
The present invention relates to the photooxidation of 2,3,5-trimethyl- phenol to yield 2,3,5-trimethylbenzoquinone using methylene blue as photo- sensitizer in a solvent mixture of water and alcohols using light of the high wavelength range of the visible spectrum.
摘要:
The present invention relates to the formation of 2,3,5-trimethylhydro- quinone from 2,3,6-tri¬methyl¬phenol comprising the steps a) the oxidation of 2,3,6-trimethylphenol to 2,3,5-trimethylquinone. b) the reduction of 2,3,5-trimethylquinone to 2,3,5-trimethylhydroquinone in such a manner that both steps a) and b) are performed in cyclic alkylene carbonate solvent.
摘要:
The present invention is directed to a process for the manufacture of 6,10,14- trimethylpentadecan-2-one ("C18-ketone") comprising the step of hydrogenating a mixture of (5E, 9E)-farnesylacetone and (5Z, 9E)- farnesylacetone with hydrogen in the presence of a catalyst, whereby the catalyst is capable of preferentially hydrogenating carbon-carbon double bonds over carbon-oxygen double bonds. Preferably the catalyst comprises a metal selected from the group consisting of palladium, platinum, rhodium, iridium and nickel and mixtures thereof.