Abstract: The present invention relates to a process of manufacturing of allene ketone using specific ammonium (thio)sulfates or hydrogen (thio)sulfates as catalyst. The reaction provides the allene ketone in high yields and selectivities.

Abstract: The application relates to a process for the preparation of a compound of formula (II) by cyclisation of a polyene of formula (I), and to an intermediate of formula (III). The obtained compounds are useful intermediates in the preparation of specific isoprenoids, preferably in the production of vitamin A and derivatives of vitamin A.

Abstract: The present invention relates to a process of manufacturing of allene ketone using specific ammonium (thio)sulfates or hydrogen (thio)sulfates as catalyst. The reaction provides the allene ketone in high yields and selectivities.

Abstract: The application relates to a process for the preparation of a compound of formula (II) by cyclisation of a polyene of formula (I), and to an intermediate of formula (III). The obtained compounds are useful intermediates in the preparation of specific isoprenoids, preferably in the production of vitamin A and derivatives of vitamin A.

Abstract: The present invention relates to the catalytic ethynlation of ??-unsaturated ketones for producing tertiary acetylenic alcohols.

Abstract: The present invention is related to a novel and improved process for the production of dehydrolinalyl acetate (DLA), which IUPAC name is acetic acid 1-ethynyl-1,5-dimethyl-hex-4-enyl ester, starting from dehydrolinalool (DLL), which IUPAC name is 3,7-dimethyloct-6-en-1-yn-3-ol, by acetylation.

Abstract: The present invention is related to a novel and improved process for the production of dehydrolinalyl acetate (DLA), which IUPAC name is acetic acid 1-ethynyl-1,5-dimethyl-hex-4-enyl ester, starting from dehydrolinalool (DLL), which IUPAC name is 3,7-dimethyloct-6-en-1-yn-3-ol, by catalytic acetylation.

Abstract: The present invention is related to a novel and improved process for the production of dehydrolinalyl acetate (DLA), which 1UPAC name is acetic acid 1-ethynyl-1,5-dimethyl-hex-4-enyl ester, starting from dehydrolinalool (DLL), which 1UPAC name is 3,7-dimethyloct-6-en-1-yn-3-ol, by acetylation.

Abstract: The present invention is related to a novel and improved process for the production of dehydrolinalyl acetate (DLA), which IUPAC name is acetic acid 1-ethynyl-1,5-dimethyl-hex-4-enyl ester, starting from dehydrolinalool (DLL), which IUPAC name is 3,7-dimethyloct-6-en-1-yn-3-ol, by catalytic acetylation.

Abstract: A process for the manufacture of gamma-delta-unsaturated ketones of formula (R1)(R2)C?CH—CH2—CH2—CO—R3 (I), wherein R1 is methyl or ethyl; R2 is a saturated or unsaturated linear or cyclic hydrocarbon residue and R3 is methyl or ethyl, by reacting a tertiary vinyl carbinol of formula (R1)(R2)C(OH)—CH?CH2 (II) with an isopropenyl methyl or ethyl ether of formula H3C—C(OR3)?CH2 (III) in the pre-sence of an ammonium salt as catalyst.

Abstract: A process for the manufacture of gamma-delta -unsaturated ketones of formula (R1)(R2)C?CH—CH2—CH2—CO—R3 (I), wherein R1 is methyl or ethyl; R2 is a saturated or unsaturated linear or cyclic hydrocarbon residue and R3 is methyl or ethyl, by reacting a tertiary vinyl carbinol of formula (R1)(R2)C(OH)—CH?CH2 (II) with an isopropenyl methyl or ethyl ether of formula H3C—C(OR3)?CH2 (Ill) in the pre-sence of an ammonium salt as catalyst.

Abstract: A process for the preparation of ubihydroquinones and ubiquinones by condensation of a prenol or isoprenol with a hydroquinone or derivative thereof in the presence of 0.005-1.0 mol % of a catalyst which is a Broensted-acid, a Lewis-acid from the group consisting of a derivative of Bi or In or an element of group 3 of the periodic table of the elements, a heteropolyacid, an NH— or a CH-acidic compound, and optionally oxidizing the ubihydroquinone obtained.

Abstract: A process for the preparation of ubihydroquinones and ubiquinones by condensation of a prenol or isoprenol with a hydroquinone or derivative thereof in the presence of 0.005-1.0 mol % of a catalyst which is a Broensted-acid, a Lewis-acid from the group consisting of a derivative of Bi or In or an element of group 3 of the periodic table of the elements, a heteropolyacid, an NH- or a CH-acidic compound, and optionally oxidizing the ubihydroquinone obtained.

Abstract: Methylheptenone (2-methyl-2-hepten-6-one) is prepared by reacting 2-methyl-3-buten-2-ol with isopropenyl methyl ether in the presence of hydrogen tris(oxalato)phosphate or hydrogen bis(oxalato)borate.

Abstract: Methylheptenone (2-methyl-2-hepten-6-one) is prepared by reacting 2-methyl-3-buten-2-ol with isopropenyl methyl ether in the presence of hydrogen tris(oxalato)phosphate or hydrogen bis(oxalato)borate.

Abstract: A process for the manufacture of d,l-&agr;-tocopherol by the acid-catalyzed condensation of trimethylhydroquinone with isophytol or phytol in ethylene or propylene carbonate or a mixture of both carbonates, or in a mixture of one or both of the carbonates and a non-polar solvent, comprises carrying out the condensation in the presence of at most 0.4 weight percent based on the weight of isophytol or phytol of 12-tungstophosphoric acid, 12-molybdophosphoric acid or 12-tungstosilicic acid. The product of the process is the most active and industrially important member of the vitamin E group.