The invention relates to Guerbet alcohol precursors and Guerbet alcohols, as well as to processes for synthesizing them.

The invention relates to Guerbet alcohol precursors and Guerbet alcohols, as well as to processes for synthesizing them.

The present invention relates to a new method to produce 7,8-dihydro-C.sub.15-aldehyde.

The present invention relates to a new method to produce 7,8-dihydro-C.sub.15-aldehyde.

Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

Process for the continuous production of an optically active carbonyl compound by asymmetric hydrogenation of a prochiral α,β-unsaturated carbonyl compound with hydrogen in the presence of a homogeneous rhodium catalyst that has at least one chiral ligand, wherein a liquid reaction mixture comprising the prochiral α,β-unsaturated carbonyl compound is subjected in a first, backmixed reactor to a gas/liquid two-phase hydrogenation, and the liquid reaction mixture is then further hydrogenated in a second reactor, wherein the prochiral α,β-unsaturated carbonyl compound is employed in the first reactor in a concentration from 3% to 20% by weight. The process allows a high total conversion to the prochiral α,β-unsaturated carbonyl compound.

Process for the continuous production of an optically active carbonyl compound by asymmetric hydrogenation of a prochiral α,β-unsaturated carbonyl compound with hydrogen in the presence of a homogeneous rhodium catalyst that has at least one chiral ligand, wherein a liquid reaction mixture comprising the prochiral α,β-unsaturated carbonyl compound is subjected in a first, backmixed reactor to a gas/liquid two-phase hydrogenation, and the liquid reaction mixture is then further hydrogenated in a second reactor, wherein the prochiral α,β-unsaturated carbonyl compound is employed in the first reactor in a concentration from 3% to 20% by weight. The process allows a high total conversion to the prochiral α,β-unsaturated carbonyl compound.

There are provided methods of efficiently producing compounds that are, for example, sex pheromones of San Jose Scale. For example, there is provided a method for producing a 7-methyl-3-methylene-7-octenyl carboxylate compound (1), the method including the step of coupling a nucleophilic reagent expressed as a 3-methyl-3-butenyl M of General Formula (8):

##STR00001##

wherein M is a cationic moiety, with an acetal compound of General Formula (9):

##STR00002##

wherein R.sup.1 and R.sup.2, which may be the same or different, are each an alkyl group having 1 to 6 carbon atoms, or are bonded to each other to form a divalent alkylene group having 2 to 12 carbon atoms, and X is a leaving group, to obtain the 7-methyl-3-methylene-7-octenal acetal compound.

There are provided methods of efficiently producing compounds that are, for example, sex pheromones of San Jose Scale. For example, there is provided a method for producing a 7-methyl-3-methylene-7-octenyl carboxylate compound (1), the method including the step of coupling a nucleophilic reagent expressed as a 3-methyl-3-butenyl M of General Formula (8):

##STR00001##

wherein M is a cationic moiety, with an acetal compound of General Formula (9):

##STR00002##

wherein R.sup.1 and R.sup.2, which may be the same or different, are each an alkyl group having 1 to 6 carbon atoms, or are bonded to each other to form a divalent alkylene group having 2 to 12 carbon atoms, and X is a leaving group, to obtain the 7-methyl-3-methylene-7-octenal acetal compound.