The present invention relates to a method for preparing a compound of formula (I). The present invention also relates to compounds of formula (A) or a compound in the form of a stereoisomer. The present invention further relates to the use of a compound of formula (A) as aroma chemical.

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The present invention relates to a method for preparing a compound of formula (I). The present invention also relates to compounds of formula (A) or a compound in the form of a stereoisomer. The present invention further relates to the use of a compound of formula (A) as aroma chemical.

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Processes are disclosed for the synthesis of a cracked product or an end product, from a starting compound or substrate having a carbonyl functional group (C═O), with hydroxy-substituted carbon atoms at alpha (α) and beta (β) positions, relative to the carbonyl functional group. According a particular embodiment, an α-, β-dihydroxy carboxylic acid or carboxylate is dehydrated to form a dicarbonyl intermediate by transformation of the α-hydroxy group to a second carbonyl group and removal of the β-hydroxy group. The dicarbonyl intermediate is cracked to form the cracked product, in which the first and second carbonyl groups are preserved. Either or both of (i) the cracked product and (ii) a second cracked product generated from cleavage of a carbon-carbon bond of the dicarbonyl intermediate, may be further converted (e.g., by hydrogenation) to one or more end products, which, like the cracked product(s), also having fewer carbon atoms relative to the dicarbonyl intermediate and substrate.

Processes are disclosed for the synthesis of a cracked product or an end product, from a starting compound or substrate having a carbonyl functional group (C═O), with hydroxy-substituted carbon atoms at alpha (α) and beta (β) positions, relative to the carbonyl functional group. According a particular embodiment, an α-, β-dihydroxy carboxylic acid or carboxylate is dehydrated to form a dicarbonyl intermediate by transformation of the α-hydroxy group to a second carbonyl group and removal of the β-hydroxy group. The dicarbonyl intermediate is cracked to form the cracked product, in which the first and second carbonyl groups are preserved. Either or both of (i) the cracked product and (ii) a second cracked product generated from cleavage of a carbon-carbon bond of the dicarbonyl intermediate, may be further converted (e.g., by hydrogenation) to one or more end products, which, like the cracked product(s), also having fewer carbon atoms relative to the dicarbonyl intermediate and substrate.

Processes are disclosed for the synthesis of a cracked product or an end product, from a starting compound or substrate having a carbonyl functional group (C═O), with hydroxy-substituted carbon atoms at alpha (α) and beta (β) positions, relative to the carbonyl functional group. According a particular embodiment, an α-, β-dihydroxy carboxylic acid or carboxylate is dehydrated to form a dicarbonyl intermediate by transformation of the α-hydroxy group to a second carbonyl group and removal of the β-hydroxy group. The dicarbonyl intermediate is cracked to form the cracked product, in which the first and second carbonyl groups are preserved. Either or both of (i) the cracked product and (ii) a second cracked product generated from cleavage of a carbon-carbon bond of the dicarbonyl intermediate, may be further converted (e.g., by hydrogenation) to one or more end products, which, like the cracked product(s), also having fewer carbon atoms relative to the dicarbonyl intermediate and substrate.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

A method including hydroformylating, with syngas, allyl alcohol in an allyl alcohol feed, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; and producing a 1,4-butanediol (BDO) product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product. A method including hydroformylating, with syngas, allyl alcohol in a feed comprising bio-allyl alcohol, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; and producing a BDO product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product. A method including hydroformylating, with syngas, bio-allyl alcohol in a feed comprising bio-allyl alcohol, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; producing a BDO product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product; and removing a byproduct of the production of the bio-allyl alcohol prior to hydroformylating the bio-allyl alcohol and/or from the BDO-product.

A method including hydroformylating, with syngas, allyl alcohol in an allyl alcohol feed, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; and producing a 1,4-butanediol (BDO) product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product. A method including hydroformylating, with syngas, allyl alcohol in a feed comprising bio-allyl alcohol, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; and producing a BDO product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product. A method including hydroformylating, with syngas, bio-allyl alcohol in a feed comprising bio-allyl alcohol, to produce a hydroformylation product comprising 4-hydroxybutyraldehyde and 3-hydroxy-2-methylpropionaldehyde; producing a BDO product comprising BDO and 1,3-methylpropanediol via hydrogenation of at least a portion of the hydroformylation product; and removing a byproduct of the production of the bio-allyl alcohol prior to hydroformylating the bio-allyl alcohol and/or from the BDO-product.