Chemoenzymatic process for coproducing a disulfide and a sulfoxide or a sulfone The present invention relates to a chemoenzymatic process for coproducing disulfide and sulfoxide or sulfone from a composition M comprising: 1) a sulfide, 2) optionally an oxidizing agent, 3) an organic compound bearing at least one thiol group, 4) an enzyme E catalyzing the oxidation of said sulfide to sulfoxide or to sulfone, 5) an enzyme D catalyzing the formation of a disulfide bridge between two equivalents of said organic compound bearing at least one thiol group to form a dimer, and 6) a cofactor common to the two enzymes E and D; and also to a composition enabling especially the implementation of this process. The present invention also relates to the use of a mercaptan for reducing a disulfide bridge formed between two equivalents of an organic compound bearing at least one thiol group, and more particularly to the use thereof as regeneration substrate of the process described above.

The invention concerns a method for treatment of a stream of mixed compounds (4a) obtained from a process (3) comprising decomposition and/or conversion of a wood or pulp material, the method comprising: feeding the stream (4a-4e) through a processing arrangement (2) comprising one or more treatment units (10, 20, 30, 40, 50) arranged to separate at least a first compound from other compounds in the stream and form a first product flow (4f) containing the first compound, wherein the one or more treatment units comprises at least a first primary separation unit (20) arranged to separate one or more compounds other than the first compound from the stream; and feeding the compounds separated from the first compound in the first primary separation unit (20) to a first auxiliary separation unit (21) so as to separate a second compound from at least one of the other compounds separated from the first compound in the first primary separation unit (20) and thereby increase the purity of said second compound and form a second product flow (22, 23) in the form of a purified second compound and/or a purified derivative of the second compound, wherein the second compound is dimethyl sulfide (DMS, CH3—S—CH3), methyl mercaptan (CH3—S—H) or acetone (CH3—CO—CH3).

The invention concerns a method for treatment of a stream of mixed compounds (4a) obtained from a process (3) comprising decomposition and/or conversion of a wood or pulp material, the method comprising: feeding the stream (4a-4e) through a processing arrangement (2) comprising one or more treatment units (10, 20, 30, 40, 50) arranged to separate at least a first compound from other compounds in the stream and form a first product flow (4f) containing the first compound, wherein the one or more treatment units comprises at least a first primary separation unit (20) arranged to separate one or more compounds other than the first compound from the stream; and feeding the compounds separated from the first compound in the first primary separation unit (20) to a first auxiliary separation unit (21) so as to separate a second compound from at least one of the other compounds separated from the first compound in the first primary separation unit (20) and thereby increase the purity of said second compound and form a second product flow (22, 23) in the form of a purified second compound and/or a purified derivative of the second compound, wherein the second compound is dimethyl sulfide (DMS, CH3—S—CH3), methyl mercaptan (CH3—S—H) or acetone (CH3—CO—CH3).

The invention concerns a method for treatment of a stream of mixed compounds (4a) obtained from a process (3) comprising decomposition and/or conversion of a wood or pulp material, the method comprising: feeding the stream (4a-4e) through a processing arrangement (2) comprising one or more treatment units (10, 20, 30, 40, 50) arranged to separate at least a first compound from other compounds in the stream and form a first product flow (4f) containing the first compound, wherein the one or more treatment units comprises at least a first primary separation unit (20) arranged to separate one or more compounds other than the first compound from the stream; and feeding the compounds separated from the first compound in the first primary separation unit (20) to a first auxiliary separation unit (21) so as to separate a second compound from at least one of the other compounds separated from the first compound in the first primary separation unit (20) and thereby increase the purity of said second compound and form a second product flow (22, 23) in the form of a purified second compound and/or a purified derivative of the second compound, wherein the second compound is dimethyl sulfide (DMS, CH3—S—CH3), methyl mercaptan (CH3—S—H) or acetone (CH3—CO—CH3).

A process for the preparation of dihalodiphenylsulfones such as 4,4′-dichlorodiphenyl sulfone or 4,4′-bis-(4-chlorophenylsulfonyl)biphenyl with high regioselectivity, at low temperature and in the absence of toxic reagents by reacting together at least one acid, at least one fluorinated anhydride and at least one halobenzene. The invented process is particularly suited for the manufacture of 4,4′-dichlorodiphenyl sulfone.

The present invention provides a method for preparing an intermediate of florfenicol, comprising: reacting p-methylthiobenzaldehyde with isocyanoacetate under catalysis of a chiral catalyst. In the reaction, the chiral product is oxidized to form a methylsulfone-substituted product which is subsequently deformylized to obtain the intermediate. In the method of the present invention, the chiral center of the intermediate is directly generated in the first step of reaction, and the yield of the first step reaches 75%-80%, which is significantly higher than the conventional chiral resolution methods (about 40% yield), and the product has high chiral purity. The method of the present invention does not use anhydrous copper sulfate that pollutes the environment, which reduces the environmental pressure. The compound of p-methylthiobenzaldehyde and the compound of isocyanoacetate are used to react to form a chiral intermediate, which has higher material availability and efficiency than linear synthesis methods.

The present invention provides a method for preparing an intermediate of florfenicol, comprising: reacting p-methylthiobenzaldehyde with isocyanoacetate under catalysis of a chiral catalyst. In the reaction, the chiral product is oxidized to form a methylsulfone-substituted product which is subsequently deformylized to obtain the intermediate. In the method of the present invention, the chiral center of the intermediate is directly generated in the first step of reaction, and the yield of the first step reaches 75%-80%, which is significantly higher than the conventional chiral resolution methods (about 40% yield), and the product has high chiral purity. The method of the present invention does not use anhydrous copper sulfate that pollutes the environment, which reduces the environmental pressure. The compound of p-methylthiobenzaldehyde and the compound of isocyanoacetate are used to react to form a chiral intermediate, which has higher material availability and efficiency than linear synthesis methods.

The present invention provides a method for preparing an intermediate of florfenicol, comprising: reacting p-methylthiobenzaldehyde with isocyanoacetate under catalysis of a chiral catalyst. In the reaction, the chiral product is oxidized to form a methylsulfone-substituted product which is subsequently deformylized to obtain the intermediate. In the method of the present invention, the chiral center of the intermediate is directly generated in the first step of reaction, and the yield of the first step reaches 75%-80%, which is significantly higher than the conventional chiral resolution methods (about 40% yield), and the product has high chiral purity. The method of the present invention does not use anhydrous copper sulfate that pollutes the environment, which reduces the environmental pressure. The compound of p-methylthiobenzaldehyde and the compound of isocyanoacetate are used to react to form a chiral intermediate, which has higher material availability and efficiency than linear synthesis methods.

The invention relates to a process for producing 4,4′-dichlorodiphenyl sulfone, comprising: (I) reacting thionyl chloride, chlorobenzene and aluminum chloride forming an intermediate reaction product and hydrogen chloride; (II) mixing aqueous hydrochloric acid and the intermediate reaction product to obtain an organic phase comprising 4,4′-dichlorodiphenyl sulfoxide and an aqueous phase; (III) cooling the organic phase to a temperature below the saturation point of 4,4′-dichlorodiphenyl sulfoxide to obtain a suspension; (IV) solid-liquid-separation of the suspension to obtain crystallized 4,4′-dichlorodiphenyl sulfoxide, and mother liquor; (V) washing the crystallized 4,4′-dichlorodiphenyl sulfoxide with a carboxylic acid to obtain carboxylic acid-wet 4,4′-dichlorodiphenyl sulfoxide; (VI) reacting the washed 4,4′-dichlorodiphenyl sulfoxide and an oxidizing agent in a carboxylic acid as solvent to obtain a reaction mixture comprising 4,4′-dichlorodiphenyl sulfone and carboxylic acid; (VII) separating the reaction mixture comprising 4,4′-dichlorodiphenyl sulfone and carboxylic acid into a residual moisture comprising 4,4′-dichlorodiphenyl sulfone as crude product and a liquid phase comprising carboxylic acid.

The invention relates to a process for producing 4,4′-dichlorodiphenyl sulfone, comprising: (I) reacting thionyl chloride, chlorobenzene and aluminum chloride forming an intermediate reaction product and hydrogen chloride; (II) mixing aqueous hydrochloric acid and the intermediate reaction product to obtain an organic phase comprising 4,4′-dichlorodiphenyl sulfoxide and an aqueous phase; (III) cooling the organic phase to a temperature below the saturation point of 4,4′-dichlorodiphenyl sulfoxide to obtain a suspension; (IV) solid-liquid-separation of the suspension to obtain crystallized 4,4′-dichlorodiphenyl sulfoxide, and mother liquor; (V) washing the crystallized 4,4′-dichlorodiphenyl sulfoxide with a carboxylic acid to obtain carboxylic acid-wet 4,4′-dichlorodiphenyl sulfoxide; (VI) reacting the washed 4,4′-dichlorodiphenyl sulfoxide and an oxidizing agent in a carboxylic acid as solvent to obtain a reaction mixture comprising 4,4′-dichlorodiphenyl sulfone and carboxylic acid; (VII) separating the reaction mixture comprising 4,4′-dichlorodiphenyl sulfone and carboxylic acid into a residual moisture comprising 4,4′-dichlorodiphenyl sulfone as crude product and a liquid phase comprising carboxylic acid.