The invention relates to a method for production of oxymethylene ether of the general formula CH.sub.3O—(CH.sub.2O).sub.m—CH.sub.3 in a liquid phase process, wherein 1≤m≤10. In a catalytic reaction, molecular oxygen or an oxygen-containing oxidant and methanol, formaldehyde, and/or methyl formate are used as reactants in a solution and are converted by means of a vanadium-oxygen compound or a salt thereof as catalyst in the solution which vanadium-oxygen compound contains vanadium in the oxidation stage +IV or +V. The catalyst reduced during the catalytic reaction is restored to its starting state by oxidation by means of the molecular oxygen or the oxygen-containing oxidant.

The invention relates to a method for production of oxymethylene ether of the general formula CH.sub.3O—(CH.sub.2O).sub.m—CH.sub.3 in a liquid phase process, wherein 1≤m≤10. In a catalytic reaction, molecular oxygen or an oxygen-containing oxidant and methanol, formaldehyde, and/or methyl formate are used as reactants in a solution and are converted by means of a vanadium-oxygen compound or a salt thereof as catalyst in the solution which vanadium-oxygen compound contains vanadium in the oxidation stage +IV or +V. The catalyst reduced during the catalytic reaction is restored to its starting state by oxidation by means of the molecular oxygen or the oxygen-containing oxidant.

The invention relates to a method for production of oxymethylene ether of the general formula CH.sub.3O—(CH.sub.2O).sub.m—CH.sub.3 in a liquid phase process, wherein 1≤m≤10. In a catalytic reaction, molecular oxygen or an oxygen-containing oxidant and methanol, formaldehyde, and/or methyl formate are used as reactants in a solution and are converted by means of a vanadium-oxygen compound or a salt thereof as catalyst in the solution which vanadium-oxygen compound contains vanadium in the oxidation stage +IV or +V. The catalyst reduced during the catalytic reaction is restored to its starting state by oxidation by means of the molecular oxygen or the oxygen-containing oxidant.

The present invention is directed to a process for the manufacture of 1,1,4,4-tetramethoxy-2-butene from 2,5-dimethoxy-2,5-dihydrofuran with methanol in the presence of an acidic ion exchanger as catalyst, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45. The present invention is further directed to a process of separating 1,1,4,4-tetramethoxy-2-butene, methanol and 2,5-dimethoxy-2,5-dihydrofuran from each other and H2O whereby a basic compound, preferably a basic metal salt or a basic ion exchanger, is present. Both processes can be carried out on an industrial scale, batch-wise or in continuous mode and are sustainable since the selectivity and the space-time-yields are high and less waste compared to known processes is produced. Further objects of the present invention are the use of a basic compound in the distillation of a mixture comprising H2O, 1,1,4,4-tetramethoxy-2-butene and 2,5-dimethoxy-2,5-dihydrofuran, as well as the use of an acidic ion exchanger as catalyst in a reaction of 2,5-dimethoxy-2,5-dihydrofuran with methanol to 1,1,4,4-tetramethoxy-2-butene, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45.

The present invention is directed to a process for the manufacture of 1,1,4,4-tetramethoxy-2-butene from 2,5-dimethoxy-2,5-dihydrofuran with methanol in the presence of an acidic ion exchanger as catalyst, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45. The present invention is further directed to a process of separating 1,1,4,4-tetramethoxy-2-butene, methanol and 2,5-dimethoxy-2,5-dihydrofuran from each other and H2O whereby a basic compound, preferably a basic metal salt or a basic ion exchanger, is present. Both processes can be carried out on an industrial scale, batch-wise or in continuous mode and are sustainable since the selectivity and the space-time-yields are high and less waste compared to known processes is produced. Further objects of the present invention are the use of a basic compound in the distillation of a mixture comprising H2O, 1,1,4,4-tetramethoxy-2-butene and 2,5-dimethoxy-2,5-dihydrofuran, as well as the use of an acidic ion exchanger as catalyst in a reaction of 2,5-dimethoxy-2,5-dihydrofuran with methanol to 1,1,4,4-tetramethoxy-2-butene, whereby the molar ratio of 2,5-dimethoxy-2,5-dihydrofuran to methanol is ≥1:45.

Method for preparing methyl formate and coproducing dimethyl ether by reacting a formaldehyde and methanol raw material (molar ratio range of 1:4 to 1:0.05) in a First Reaction Region at ranges from 50° C. to 100° C. with Catalyst A resulting in post-reaction material separated into Constituent I. Reacting Constituent I in a Second Reaction Region at ranges from 50° C. to 200° C. and from 0.1 MPa to 10 MPa with Catalyst B resulting in post-reaction material, which is separated into methyl formate, dimethyl ether and Constituent II. At least 1% of dimethyl ether is product, and recycling the rest to the First Reaction Region. Constituent II is recycled to the Second Reaction Region. Each component is gaseous phase and/or liquid phase, independently. The method shows long catalyst life, mild reaction condition, high utilization ratio of raw materials, continuous production and large scale industrial application potential.

Method for preparing methyl formate and coproducing dimethyl ether by reacting a formaldehyde and methanol raw material (molar ratio range of 1:4 to 1:0.05) in a First Reaction Region at ranges from 50° C. to 100° C. with Catalyst A resulting in post-reaction material separated into Constituent I. Reacting Constituent I in a Second Reaction Region at ranges from 50° C. to 200° C. and from 0.1 MPa to 10 MPa with Catalyst B resulting in post-reaction material, which is separated into methyl formate, dimethyl ether and Constituent II. At least 1% of dimethyl ether is product, and recycling the rest to the First Reaction Region. Constituent II is recycled to the Second Reaction Region. Each component is gaseous phase and/or liquid phase, independently. The method shows long catalyst life, mild reaction condition, high utilization ratio of raw materials, continuous production and large scale industrial application potential.

Provided are a terminal conjugated trienal acetal compound useful as an intermediate for producing a terminal conjugated trienal compound, and a method for producing a terminal conjugated trienal compound through deprotection of the terminal conjugated trienal acetal compound. More specifically, provided are a terminal conjugated trienal acetal compound represented by General Formula (1); a method for producing a (Z,E)-terminal conjugated trienal acetal compound, the method comprising the step of: reacting a phosphonium salt represented by General Formula (7) with (E)-2,4-pentadienal through Wittig reaction to obtain a (Z,E)-terminal conjugated trienal acetal compound represented by General Formula (3); and a method for producing a terminal conjugated trienal compound, the method comprising the step of: deprotecting the terminal conjugated trienal acetal compound represented by General Formula (1) to obtain a terminal conjugated trienal compound represented by General Formula (2).

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Provided are a terminal conjugated trienal acetal compound useful as an intermediate for producing a terminal conjugated trienal compound, and a method for producing a terminal conjugated trienal compound through deprotection of the terminal conjugated trienal acetal compound. More specifically, provided are a terminal conjugated trienal acetal compound represented by General Formula (1); a method for producing a (Z,E)-terminal conjugated trienal acetal compound, the method comprising the step of: reacting a phosphonium salt represented by General Formula (7) with (E)-2,4-pentadienal through Wittig reaction to obtain a (Z,E)-terminal conjugated trienal acetal compound represented by General Formula (3); and a method for producing a terminal conjugated trienal compound, the method comprising the step of: deprotecting the terminal conjugated trienal acetal compound represented by General Formula (1) to obtain a terminal conjugated trienal compound represented by General Formula (2).

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This application is directed to use of transition metal-ligand complexes to hydrogenate fluorinated esters and carboxamides into fluorinated hemiacetals. Methods for synthesis of certain ligands are also provided.