Tetrafluorohydroquinone

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0 to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0° to 5° C. for 30 minutes to obtain 1,4-bis (3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60 % sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis (3,4-dicarboxytrifluorophenoxy) tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis (3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80 % sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0° to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0° to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2.0 g (11.0 mM) of 2,3,5,6-tetrafluorohydroquinone, 0.87 g (5.5 mM) of nonanoic acid, 1.13 g (5.5 mM) of dicyclohexylcarbodiimide and a catalytic amount of 4-pyrrolidinopyridine were added to 20 ml of tetrahydrofuran, followed by stirring for 3 hours at room temperature. After the reaction, the insoluble residue was filtered off, followed by distilling-off of the solvent to obtain a crude product. The crude product was purified by silica gel column chromatography (eluent: toluene) to obtain 0.57 g of an objective product (Yield: 32.2%). After the reaction the insoluble residue was filtered off to obtain a crude product The crude product was purified by silica gel column chromatography (eluent: toluene)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0° to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0° to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: More specifically, in Reaction Scheme-7, tetrafluorophthalonitrile and tetrafluorohydroquinone (or its metal salts, e.g., disodium salt) are reacted usually in the presence of a base (for example, trimethylamine, etc.) in a polar solvent at 0 to 5° C. for 30 minutes to obtain 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene, which is then hydrolyzed, for example, in an aqueous 60% sulfuric acid solution at 150° C. for 15 hours to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene. Refluxing the product in acetic anhydride for 2 hours results in dehydration to give 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride. Also, 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene may be heated, for example, in an aqueous 80% sulfuric acid solution at 200° C. for 2 hours to effect hydrolysis and dehydration in one step to obtain 1,4-bis(3,4-dicarboxytrifluorophenoxytetrafluorobenzene dianhydride.