A catalyst having coke wherein the coke, upon analysis by infrared spectroscopy in diffuse reflection, has at least two peaks at a wavelength between 1450 cm.sup.−1 and 1700 cm.sup.−1.

The aforesaid catalyst having coke can be advantageously used in a process for the production of a diene, preferably a conjugated diene, more preferably 1,3-butadiene, said process having the dehydration of at least one alkenol having a number of carbon atoms greater than or equal to 4.

Preferably, the alkenol having a number of carbon atoms greater than or equal to 4 can be obtained directly from biosynthetic processes, or through catalytic dehydration processes of at least one diol.

When the alkenol is a butenol, the diol is preferably a butanediol, more preferably 1,3-butanediol, even more preferably bio-1,3-butanediol, i.e. 1,3-butanediol deriving from biosynthetic processes.

When the diol is 1,3-butanediol, or bio-1,3-butanediol, the diene obtained with the process is, respectively, 1,3-butadiene, or bio-1,3-butadiene.

A catalyst having coke wherein the coke, upon analysis by infrared spectroscopy in diffuse reflection, has at least two peaks at a wavelength between 1450 cm.sup.−1 and 1700 cm.sup.−1.

The aforesaid catalyst having coke can be advantageously used in a process for the production of a diene, preferably a conjugated diene, more preferably 1,3-butadiene, said process having the dehydration of at least one alkenol having a number of carbon atoms greater than or equal to 4.

Preferably, the alkenol having a number of carbon atoms greater than or equal to 4 can be obtained directly from biosynthetic processes, or through catalytic dehydration processes of at least one diol.

When the alkenol is a butenol, the diol is preferably a butanediol, more preferably 1,3-butanediol, even more preferably bio-1,3-butanediol, i.e. 1,3-butanediol deriving from biosynthetic processes.

When the diol is 1,3-butanediol, or bio-1,3-butanediol, the diene obtained with the process is, respectively, 1,3-butadiene, or bio-1,3-butadiene.

The presently claimed invention relates to a process for the recovery of 3-methyl-3-buten- -ol from a stream comprising (Z)-3-methylpent-2-ene-1,5-diol, (E)-3-methylpent-2-ene-,5-diol and 3-methylenepentane-1,5-diol by treating the stream with isobutene and water.

The presently claimed invention relates to a process for the recovery of 3-methyl-3-buten- -ol from a stream comprising (Z)-3-methylpent-2-ene-1,5-diol, (E)-3-methylpent-2-ene-,5-diol and 3-methylenepentane-1,5-diol by treating the stream with isobutene and water.

Compositions comprising 3-hexen-1-ol are described herein, as well as odor-imparting formulations comprising same and articles-of-manufacturing comprising such compositions or odor-imparting formulations. The compositions comprise trans-3-hexen-1-ol in a range of from 67% to 82% by weight and cis-3-hexen-1-ol in a range of from 18% to 33% by weight, wherein a total concentration of trans-3-hexen-1-ol and cis-3-hexen-1-ol is at least 97% by weight. Further described herein is a process for preparing a composition comprising 3-hexen-1-ol, the process comprising: contacting 1-pentene with a formaldehyde in the presence of a Lewis acid to thereby obtain a crude mixture comprising 3-hexen-1-ol; and contacting the mixture comprising 3-hexen-1-ol with a base.

Compositions comprising 3-hexen-1-ol are described herein, as well as odor-imparting formulations comprising same and articles-of-manufacturing comprising such compositions or odor-imparting formulations. The compositions comprise trans-3-hexen-1-ol in a range of from 67% to 82% by weight and cis-3-hexen-1-ol in a range of from 18% to 33% by weight, wherein a total concentration of trans-3-hexen-1-ol and cis-3-hexen-1-ol is at least 97% by weight. Further described herein is a process for preparing a composition comprising 3-hexen-1-ol, the process comprising: contacting 1-pentene with a formaldehyde in the presence of a Lewis acid to thereby obtain a crude mixture comprising 3-hexen-1-ol; and contacting the mixture comprising 3-hexen-1-ol with a base.

Compositions comprising 3-hexen-1-ol are described herein, as well as odor-imparting formulations comprising same and articles-of-manufacturing comprising such compositions or odor-imparting formulations. The compositions comprise trans-3-hexen-1-ol in a range of from 67% to 82% by weight and cis-3-hexen-1-ol in a range of from 18% to 33% by weight, wherein a total concentration of trans-3-hexen-1-ol and cis-3-hexen-1-ol is at least 97% by weight. Further described herein is a process for preparing a composition comprising 3-hexen-1-ol, the process comprising: contacting 1-pentene with a formaldehyde in the presence of a Lewis acid to thereby obtain a crude mixture comprising 3-hexen-1-ol; and contacting the mixture comprising 3-hexen-1-ol with a base.

The disclosure relates to dicarbonyl complexes of ruthenium and osmium with bi- and tridentate nitrogen and phosphine ligands. The disclosure relates to methods for preparing these complexes and the use of these complexes, isolated or prepared in situ, as catalysts for reduction reactions of ketones and aldehydes both via transfer hydrogenation or hydrogenation with hydrogen.

The disclosure relates to dicarbonyl complexes of ruthenium and osmium with bi- and tridentate nitrogen and phosphine ligands. The disclosure relates to methods for preparing these complexes and the use of these complexes, isolated or prepared in situ, as catalysts for reduction reactions of ketones and aldehydes both via transfer hydrogenation or hydrogenation with hydrogen.

A compound according to formula IIa, which is (S,Z)-3,7-dimethylnon-6-en-1-ol and its use as fragrance.

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