4,6-diaminobenzene-1,3-diol

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: After the active carbon treatment, solids are deposited by salting out with addition of concentrated hydrochloric acid, and an amount of added hydrochloric acid may be 4-20 times by mole of 4,6-diaminoresorcinol. It is influenced by the amount of water from the economical viewpoint, but 4-8 times by mole are preferable. 4,6-Diaminoresorcinol dihydrochloride is obtained by drying after filtration.

反応条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: The crude diaminoresorcinol (57.0 g), from Step A, containing the Pd/C catalyst, is dissolved in 400 g of 6% aqueous HCl at 80° C. The catalyst is removed by filtration. An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the diaminoresorcinol mixture along with 5.0 g of activated carbon. The solution is heated at reflux for 15 minutes and then the carbon is removed by filtration. The filtrate is cooled to 0° C. to allow crystallization of the product. The resulting white precipitate is isolated by filtration under a purge of dry nitrogen. This filter cake is then dried in vacuo at 40° C. to a constant weight to yield 48.7 g of essentially pure (99.8%) 4,6-diaminoresorcinol dihydrochloride having a m.p. of >300° C. Elemental Anal. calc'd for C6H10Cl2N2O2 (213.0643): C, 33.82; H, 4.73; Cl, 33.28; N, 13.15; 0, 15.02, found: C, 33.6; H, 4.64; N, 13.20. The catalyst is removed by filtration An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the diaminoresorcinol mixture along with 5.0 g of activated carbon The solution is heated at reflux for 15 minutes the carbon is removed by filtration crystallization of the product The resulting white precipitate is isolated by filtration under a purge of dry nitrogen This filter cake is then dried in vacuo at 40° C. to a constant weight

反応条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: The crude diaminoresorcinol (57.0 g), from Step A, containing the Pd/C catalyst, is dissolved in 400 g of 6% aqueous HCl at 80° C. The catalyst is removed by filtration. An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the diaminoresorcinol mixture along with 5.0 g of activated carbon. The solution is heated at reflux for 15 minutes and then the carbon is removed by filtration. The filtrate is cooled to 0° C. to allow crystallization of the product. The resulting white precipitate is isolated by filtration under a purge of dry nitrogen. This filter cake is then dried in vacuo at 40° C. to a constant weight to yield 48.7 g of essentially pure (99.8%) 4,6-diaminoresorcinol dihydrochloride having a m.p. of >300° C. Elemental Anal. calc'd for C6H10Cl2N2O2 (213.0643): C, 33.82; H, 4.73; Cl, 33.28; N, 13.15; 0, 15.02, found: C, 33.6; H, 4.64; N, 13.20. The catalyst is removed by filtration An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the diaminoresorcinol mixture along with 5.0 g of activated carbon The solution is heated at reflux for 15 minutes the carbon is removed by filtration crystallization of the product The resulting white precipitate is isolated by filtration under a purge of dry nitrogen This filter cake is then dried in vacuo at 40° C. to a constant weight

反応条件: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 4,6-Diamino-1,3-benzenediol dihydrochloride (2.1279 g, 10.0 mmol), 2-benzothiazole terephthalic acid (2.9891 g, 10.0 mmol) and 9.96 g of polyphosphoric acid (77% P2O5) were placed in a resin flask equipped with a mechanical stirrer, nitrogen inlet/outlet tubes, a vacuum connector and a side opening on the resin flask. The solution was heated at 90° C. in vacuo for 20 hours for dehydrochlorination. The reaction mixture was cooled to 50° C., then 6.04 g of P2O5 was added, in vacuo, thereby raising the polymer concentration to 18%. After adding the P2O5, heating was resumed. The mixture was heated at 174° C. for 16 hours, then at 190° C. for 24 hours. Work-up, as in the preceeding Example, gave 3.2 g of polymer with [N]=4.1 dl/g, methanesulfonic acid at 30° C. equipped with a mechanical stirrer, nitrogen inlet/outlet tubes The reaction mixture was cooled to 50° C. raising the polymer concentration to 18% After adding the P2O5 heating The mixture was heated at 174° C. for 16 hours at 30° C.

反応条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: The crude dihydrochloride salt of 4,6-diaminoresorcinol (57.0 g) containing 10% Pd/C catalyst is dissolved in 400 g of 6% (by weight) aqueous HCl at 80° C. The catalyst present is removed by filtration. An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the product mixture along with 5.0 g of activated carbon. The solution is heated at reflux for 15 minutes and the carbon is then removed by filtration. The filtrate is cooled to 0° C. to allow crystallization of the monomer. The resulting precipitate is isolated by filtration under a purge of dry nitrogen. This filter cake is then dried in vacuo at 40° C. to a constant weight to yield 48.7 g of essentially pure (99.8%) 4,6-diaminoresorcinol dihydrochloride having an m.p. of >300° C. with decomposition. Elemental Anal. calc'd for C6H10Cl2N2O2 (213.0642): C, 33.82; H, 4.73; Cl, 33.28; N, 13.15; O, 15.02, found: C, 33.6; H, 4.64; N, 13.20. The catalyst present is removed by filtration An additional 50.0 g of concentrated HCl containing 1.5 g of stannous chloride dihydrate is added to the product mixture along with 5.0 g of activated carbon The solution is heated at reflux for 15 minutes the carbon is then removed by filtration crystallization of the monomer The resulting precipitate is isolated by filtration under a purge of dry nitrogen This filter cake is then dried in vacuo at 40° C. to a constant weight

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: In a preferred embodiment for making diaminoresorcinol, the base, e.g., sodium hydroxide, is first dissolved in refluxing liquid ammonia in an inert atmosphere. The temperature of refluxing liquid ammonia is dependent upon the pressure and is typically between about -50° C. to about -10° C. Under atmospheric pressure conditions, the refluxing temperature of liquid ammonia is about -33° C. A solution of cumene hydroperoxide and 1,2-dichloro-3,5-dinitrobenzene in methylene chloride is then added to the stirred liquid ammonia reaction mixture at a rate such that the temperature remains at the refluxing temperature. Upon completion of the addition, the ammonia is evaporated and 2,3-dichloro-4,6-dinitrophenol may be isolated by pouring the reaction mixture into excess aqueous hydrochloric acid and extracted with ethyl acetate. Preferably, the 2,3-dichloro-4,6-dinitrophenol product is not isolated or purified, but is directly converted to 4,6-diaminoresorcinol, thus making the production of 4,6-diaminoresorcinol from 1,2-dichloro-3,5-dinitrobenzene a "one pot" process. is typically between about -50° C. to about -10° C is about -33° C Upon completion of the addition the ammonia is evaporated

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Because of the difficulties mentioned it has been tried to obtain diaminoresorcinol from another starting material. Thus, in EP 266,222 it is proposed to nitrate 1,2,3-trichlorobenzene in a sulphuric acid/nitric acid mixture to 1,2,3-trichloro-4,6-dinitro-benzene and to convert this compound, using an alkali metal hydroxide in methanol/water, into 1,3-dihydroxy-2-chloro-4,6-dinitrobenzene. The reduction of the latter compound on a Pd/activated charcoal catalyst gives diaminoresorcinol. However this process has the disadvantage that the dihydroxy compound of the second process step must be extracted with ethyl acetate, as a consequence of which the space yield drops to about 75 g/l (0.32 mole/l); after the said extraction the dihydroxy compound is isolated by evaporation of the ethyl acetate phase.

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: After the active carbon treatment, solids are deposited by salting out with addition of concentrated hydrochloric acid, and an amount of added hydrochloric acid may be 4-20 times by mole of 4,6-diaminoresorcinol. It is influenced by the amount of water from the economical viewpoint, but 4-8 times by mole are preferable. 4,6-Diaminoresorcinol dihydrochloride is obtained by drying after filtration.