2,3,5,6-tetrachlorobenzene-1,4-diol

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a 500 ml 4-necked flask, were poured 71.15 g (355 mmol) of tetrafluorophthalonitrile, 2.16 g (37.1 mmol) of potassium fluoride and 210 g of acetonitrile, and resulting was heated to 80° C. This mixture was kept at 80° C. with stirring, and to this mixture were dropped 4.40 g (17.7 mmol) of tetrachlorohydroquinone in 200 ml of acetonitrile over 1 hour. After dropping, reaction was performed at 80° C. for 6 hours. The reaction solution was cooled, filtrated, and the resulting residue washed with 30 ml and 15 ml of acetonitrile. After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo. To this was poured 27 ml of toluene and reflux performed for 1 hour. After cooling, the residue was washed with 5 ml, 25 ml and 5 ml of toluene, respectively, and further 12 ml of deionized water for three times. Finally, by drying the residue at 70° C. in vacuo, 9.08 g of 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene were obtained (yield: 84%). resulting was kept at 80° C. reaction The reaction solution was cooled filtrated the resulting residue washed with 30 ml and 15 ml of acetonitrile After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo To this was poured 27 ml of toluene reflux performed for 1 hour After cooling the residue was washed with 5 ml, 25 ml and 5 ml of toluene Finally, by drying the residue at 70° C. in vacuo

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

Procedure: The objective 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene dianhydride is produced as an embodiment by reacting tetrafluorophthalonitrile and tetrachlorohydroquinone (or its metal salts such as 2 Na salt; it is summarized as “tetrachlorohydroquinone”) in the presence of a base in a solvent at a temperature of −20° C. to 200° C. for 0.1 to 20 hours to form 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene (Step 1a); hydrolyzing the resulting 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene with an acid at a temperature of 50° C. to 300° C. for 0.5 to 20 hours to form 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1b); dissolving the reaction solution including 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene in a medium containing an organic solvent once, purifying and separating the product therefrom (Step 1c); and then dehydrating the separated 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1d). at a temperature of −20° C. to 200° C. for 0.1 to 20 hours

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

Procedure: The objective 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene dianhydride is produced as an embodiment by reacting tetrafluorophthalonitrile and tetrachlorohydroquinone (or its metal salts such as 2 Na salt; it is summarized as “tetrachlorohydroquinone”) in the presence of a base in a solvent at a temperature of −20° C. to 200° C. for 0.1 to 20 hours to form 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene (Step 1a); hydrolyzing the resulting 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene with an acid at a temperature of 50° C. to 300° C. for 0.5 to 20 hours to form 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1b); dissolving the reaction solution including 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene in a medium containing an organic solvent once, purifying and separating the product therefrom (Step 1c); and then dehydrating the separated 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1d). at a temperature of −20° C. to 200° C. for 0.1 to 20 hours

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

Procedure: Re 1 A very large excess of hydrochloric acid (96 times the molar quantity) is required, and a very high salt load results due to the addition of 7.4 times the molar quantity of magnesium chloride. Furthermore, the prescribed temperature/time control during the addition of hydrogen peroxide cannot be maintained because of the high heat of reaction. A repeat of this process using only 30 times the molar quantity of hydrochloric acid, 3 times the molar quantity of magnesium chloride and more suitable temperature control gave a qualitatively poor chloranil (melting point 215°-220° C., yield 95% of theory) with trichloro-1,4-benzoquinone and tetrachlorohydroquinone as impurities. cannot be maintained because of the high heat of reaction

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

Procedure: After 146 parts (2.1 mol) of chlorine gas have been introduced over a period of 7.5 hours, a thick, light beige-colored suspension composed predominantly of tetrachlorohydroquinone, is obtained at the temperature level of 95° C. 21 parts of chlorine were found in the off-gas. After a further 84 parts (1.2 mol) of chlorine gas have been introduced over a period of a further 8 hours, a thin, light yellow suspension is obtained at the temperature level of 105° C., from which 106.4 parts of chloranil having a melting point of 255° to 260° C. are isolated under the working-up conditions according to the example. The chloranil still contains significant amounts of mono-, di- and tetra-chlorohydroquinone. is obtained at the temperature level of 95° C

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

Procedure: Re 1: A very large excess of hydrochloric acid (96 times the molar quantity) is required, and a very high salt load results due to the addition of 7.4 times the molar quantity of magnesium chloride. Furthermore, the prescribed temperature/time control during the addition of hydrogen peroxide cannot be maintained because of the high heat of reaction. A repeat of this process using only 30 times the molar quantity of hydrochloric acid, 3 times the molar quantity of magnesium chloride and more suitable temperature control gave a qualitatively poor chloranil (melting point 215°-220° C., yield 95% of theory) with trichloro-1,4-benzoquinone and tetrachlorohydroquinone as impurities. cannot be maintained because of the high heat of reaction

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a 500 ml 4-necked flask, were poured 71.15 g (355 mmol) of tetrafluorophthalonitrile, 2.16 g (37.1 mmol) of potassium fluoride and 210 g of acetonitrile, and resulting was heated to 80° C. This mixture was kept at 80° C. with stirring, and to this mixture were dropped 4.40 g (17.7 mmol) of tetrachlorohydroquinone in 200 ml of acetonitrile over 1 hour. After dropping, reaction was performed at 80° C. for 6 hours. The reaction solution was cooled, filtrated, and the resulting residue washed with 30 ml and 15 ml of acetonitrile. After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo. To this was poured 27 ml of toluene and reflux performed for 1 hour. After cooling, the residue was washed with 5 ml, 25 ml and 5 ml of toluene, respectively, and further 12 ml of deionized water for three times. Finally, by drying the residue at 70° C. in vacuo, 9.08 g of 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene were obtained (yield: 84%). resulting was kept at 80° C. reaction The reaction solution was cooled filtrated the resulting residue washed with 30 ml and 15 ml of acetonitrile After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo To this was poured 27 ml of toluene reflux performed for 1 hour After cooling the residue was washed with 5 ml, 25 ml and 5 ml of toluene Finally, by drying the residue at 70° C. in vacuo

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

Procedure: The objective 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene dianhydride is produced as an embodiment by reacting tetrafluorophthalonitrile and tetrachlorohydroquinone (or its metal salts such as 2 Na salt; it is summarized as “tetrachlorohydroquinone”) in the presence of a base in a solvent at a temperature of −20° C. to 200° C. for 0.1 to 20 hours to form 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene (Step 1a); hydrolyzing the resulting 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene with an acid at a temperature of 50° C. to 300° C. for 0.5 to 20 hours to form 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1b); dissolving the reaction solution including 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene in a medium containing an organic solvent once, purifying and separating the product therefrom (Step 1c); and then dehydrating the separated 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1d). at a temperature of −20° C. to 200° C. for 0.1 to 20 hours

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a 500 ml 4-necked flask, were poured 71.15 g (355 mmol) of tetrafluorophthalonitrile, 2.16 g (37.1 mmol) of potassium fluoride and 210 g of acetonitrile, and resulting was heated to 80° C. This mixture was kept at 80° C. with stirring, and to this mixture were dropped 4.40 g (17.7 mmol) of tetrachlorohydroquinone in 200 ml of acetonitrile over 1 hour. After dropping, reaction was performed at 80° C. for 6 hours. The reaction solution was cooled, filtrated, and the resulting residue washed with 30 ml and 15 ml of acetonitrile. After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo. To this was poured 27 ml of toluene and reflux performed for 1 hour. After cooling, the residue was washed with 5 ml, 25 ml and 5 ml of toluene, respectively, and further 12 ml of deionized water for three times. Finally, by drying the residue at 70° C. in vacuo, 9.08 g of 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene were obtained (yield: 84%). resulting was kept at 80° C. reaction The reaction solution was cooled filtrated the resulting residue washed with 30 ml and 15 ml of acetonitrile After the filtrate had been concentrated on an evaporator to remove the solvent, 62.34 g of tetrafluorophthalonitrile was removed under in vacuo To this was poured 27 ml of toluene reflux performed for 1 hour After cooling the residue was washed with 5 ml, 25 ml and 5 ml of toluene Finally, by drying the residue at 70° C. in vacuo

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

Procedure: The objective 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene dianhydride is produced as an embodiment by reacting tetrafluorophthalonitrile and tetrachlorohydroquinone (or its metal salts such as 2 Na salt; it is summarized as “tetrachlorohydroquinone”) in the presence of a base in a solvent at a temperature of −20° C. to 200° C. for 0.1 to 20 hours to form 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene (Step 1a); hydrolyzing the resulting 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrachlorobenzene with an acid at a temperature of 50° C. to 300° C. for 0.5 to 20 hours to form 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1b); dissolving the reaction solution including 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene in a medium containing an organic solvent once, purifying and separating the product therefrom (Step 1c); and then dehydrating the separated 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrachlorobenzene (Step 1d). at a temperature of −20° C. to 200° C. for 0.1 to 20 hours