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##

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 preparing polyoxymethylene dimethyl ethers having 3 oxymethylene units (OME.sub.n3), comprising the steps:

(i) introduction of formaldehyde, methanol and water into a reactor R and reaction to give a reaction mixture containing formaldehyde, water, methylene glycol, polyoxymethylene glycols, methanol, hemiformals, methylal (OME.sub.n=1) and polyoxymethylene dimethyl ethers (OME.sub.n>1);
(ii) introduction of the reaction mixture into a reactive distillation column K1 and separation into a low boiler fraction F1 containing formaldehyde, water, methylene glycol, polyoxymethylene glycols, methanol, hemiformals, methylal (OME.sub.n=1) and polyoxymethylene dimethyl ethers having from 2 to 3 oxymethylene units (OME.sub.n=2-3) and a high boiler fraction F2 containing polyoxymethylene dimethyl ethers having more than two oxymethylene units (OME.sub.n3).

The present invention relates to the field of perfumery. More particularly, it concerns valuable new chemical intermediates for producing perfuming ingredients. Moreover, the present invention comprises also a process for producing compound of formula (I).

The present invention relates to the field of perfumery. More particularly, it concerns valuable new chemical intermediates for producing perfuming ingredients. Moreover, the present invention comprises also a process for producing compound of formula (I).

The present invention relates to a process of manufacturing (6R,10R)-6,10,14-trimethylpentadecan-2-one in a multistep synthesis from a mixture of (5E,9E)-, (5E,9Z)-, (5Z,9E)- and (5Z.9Z)-isomers of 6,10,14-trimethylpentadeca-5,9,13-trien-2-one or 6,10,14-trimethylpentadeca-5,9-dien-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.

The present invention relates to a process of manufacturing (6R,10R)-6,10,14-trimethylpentadecan-2-one in a multistep synthesis from a mixture of (5E,9E)-, (5E,9Z)-, (5Z,9E)- and (5Z.9Z)-isomers of 6,10,14-trimethylpentadeca-5,9,13-trien-2-one or 6,10,14-trimethylpentadeca-5,9-dien-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.

The present invention relates to a process of manufacturing (6R,10R)-6,10,14-trimethylpentadecan-2-one in a multistep synthesis from a mixture of (5E,9E)-, (5E,9Z)-, (5Z,9E)- and (5Z.9Z)-isomers of 6,10,14-trimethylpentadeca-5,9,13-trien-2-one or 6,10,14-trimethylpentadeca-5,9-dien-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.

Disclosed is a preparation method for an SGLT2 inhibitor intermediate V, the method comprising: adding a compound IV to a solvent, and in the presence of a catalytic reagent, carrying out heat preservation reaction with a fluorination reagent. The preparation process for the intermediate V is simple in operations, mild in reaction conditions and high in safety, facilitates quality control and is suitable for industrial production. In addition, the intermediate V prepared by the method is high in purity, has few side reaction product monofluoro-impurity shown as structural Formula V, is easy to purify, and is applicable to quality research on active pharmaceutical ingredients and preparations of the SGLT2 inhibitor.