anthracene-1,4-diol

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

Procedure: A solution of sodium hydrosulfite (16.70 g, 42.0 mmol, 1 molar equivalent) in a water/dioxane (3/2) (250 mL) mixture is added under nitrogen to the 1,4-anthracenedione 1a (5.00 g, 24.0 mmol, 1 molar equivalent). The resulting mixture is stirred at room temperature for 3 h. Water is added and the resulting precipitate is filtered, washed with water and dried under vacuum to give the title compound as a yellow powder (3.10 g, 61%). 1H NMR (300.13 MHz, THF-d8) (ppm) 6.53 (s, 2H) 7.34-7.40 (m, 2H) 7.96-7.99 (m, 2H) 8.65 (s, 2H) 8.70 (s, 2H). the resulting precipitate is filtered washed with water dried under vacuum

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 0.275 g (11.0 mmol) of pre-washed (with distilled diethyl ether) sodium hydride under argon were added 1.00 g (4.80 mmol) of 1,4-dihydroxyanthracene, 0.75 mL (12.0 mmol) of iodomethane, and 10 mL of DMF (distilled over CaH2). The solution was stirred at 25° C. for 1.5 h, diluted with 20 mL of water, and acidified with 6 N HCl (pH ˜2). The mixture was extracted three times with ethyl acetate, and the combined extract was washed twice with water, and brine, dried (MgSO4), concentrated to give 1.07 g (94% yield) of compound 2. Recrystallization from ether:hexane (1:1) gave 0.89 g (78% yield) of yellow solids: mp 132-133° C. (Lit.6 134-136° C.); MS, FAB, m/z 239 (M+1), 238 (M+); 1H NMR d 8.70 (s, 2H, C9,10H), 7,97 (dd, J=6.1, 3.6 Hz, 2H, C5,8H), 7.40 (dd, J=6.6, 3.2 Hz, 2H, C6,7H ), 6.55 (s, 2H, C2,3H), 3.97 (s, 6H, OCH3); 13C NMR d 149.5 (s, C8a,10a), 131.5 (s, C4a,9a), 128.5 (d, C9,10), 125.5 (d, C5,8), 120.7 (d, C6,7), 100.9 (d, C2,3), 55.6 (s, OCH3). To a 0.275 g (11.0 mmol) of pre-washed (with distilled diethyl ether) sodium hydride under argon The mixture was extracted three times with ethyl acetate the combined extract was washed twice with water, and brine dried (MgSO4) concentrated

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 2.00 g (1.00 mmol) of 1,4-anthracenedione, a solution of 6.68 g (38.0 mmol) of sodium hydrosulfite in 50 mL of water and 50 mL of 1,4-dioxane was added. The resulting mixture was stirred at 25° C. for 3 h, and added 100 mL of water. The mixture was cooled over an ice-water bath, and the precipitated dark green solids were collected by filtration, washed twice with water, and dried under vacuum to give 1.75 g (87% yield) of 1,4-dihydroxyanthracene, mp 167-169° C.; 1H NMR d 8.70 (s, 2H, C 9,10 Hs), 8.05 (m, 2H, C 5,8 Hs), 7.50 (s, 2H, C 6,7 Hs), 6.60 (s, 2H, C 2,3 Hs). The mixture was cooled over an ice-water bath the precipitated dark green solids were collected by filtration washed twice with water dried under vacuum

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 0.275 g (11.0 mmol) of pre-washed (with distilled diethyl ether) sodium hydride under argon were added 1.00 g (4.80 mmol) of 1,4-dihydroxyanthracene, 0.75 mL (12.0 mmol) of iodomethane, and 10 mL of DMF (distilled over CaH2). The solution was stirred at 25° C. for 1.5 h, diluted with 20 mL of water, and acidified with 6 N HCl (pH ˜2). The mixture was extracted three times with ethyl acetate, and the combined extract was washed twice with water, and brine, dried (MgSO4), concentrated to give 1.07 g (94% yield) of compound 2. Recrystallization from ether:hexane (1:1) gave 0.89 g (78% yield) of yellow solids: mp 132-133° C. (Lit.6 134-136° C.); MS, FAB, m/z 239 (M+1), 238 (M+); 1H NMR d 8.70 (s, 2H, C9,10H), 7,97 (dd, J=6.1, 3.6 Hz, 2H, C5,8H), 7.40 (dd, J=6.6, 3.2 Hz, 2H, C6,7H ), 6.55 (s, 2H, C2,3H), 3.97 (s, 6H, OCH3); 13C NMR d 149.5 (s, C8a,10a), 131.5 (s, C4a,9a), 128.5 (d, C9,10), 125.5 (d, C5,8), 120.7 (d, C6,7), 100.9 (d, C2,3), 55.6 (s, OCH3). To a 0.275 g (11.0 mmol) of pre-washed (with distilled diethyl ether) sodium hydride under argon The mixture was extracted three times with ethyl acetate the combined extract was washed twice with water, and brine dried (MgSO4) concentrated

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

Procedure: In the reported synthesis of 5,8-disubstituted triptycene monoquinones, (Bartlett, P. D.; Ryan, M. J.; Cohen, S. G. J. Am. Chem. Soc. 1942, 64, 2649; Skvarehenko, V. R.; Shalaev, V. K.; Klabunovskii, E. I. Russ. Chem. Rev. 1974, 43, 951; Iwamura, H.; Maino, K. An intramolecular triptycene quinhydrone. J. Chem. Soc. Chem. Commun. 1978, 720.; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 1016-1038; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 2414; Patney, H. K. Synthesis 1991, 694. Charge-transfer complexes; Lipczynska-Kochany, E.; Iwamura, H. Chem. Lett. 1982, 1075; Daub, J.; Jakob, L.; Salbeck, J. Chem. Ber. 1988, 121, 2187. Radical Anions: Russell, G. A.; Suleman, N. K. J. Am. Chem. Soc. 1981, 103, 1560-1561. Liquid Crystals; Norvez, S. J. Org. Chem. 1993, 58, 2414) a sequence of three reactions was carried out: Diels-Alder reaction of 1,4-dimethoxyanthracene (Criswell, T. R.; Klanderman, B. H. J. Org. Chem. 1974, 39, 770) and p-benzoquinone followed by isomerization of the adducts (endo- and exo-adducts) with potassium hydroxide and then oxidation with silver oxide. These three reactions have been successfully combined into one simple operation. Hence, heating of anthracene 2 (derived from the reduction of 1,4-anthracenedione (Perchellet, E. M.; Magill, M. J.; Huang, X.; Brantis, C. E.; Hua, D. H.; Perchellet, J. P. Anti-cancer Drugs, 1999, 10, 749) with sodium hydrosulfite followed by sodium hydride and iodomethane), 1.4 equiv of methoxyhydroquinone (3), 2.7 equiv of silver oxide, and 0.2 equiv of zinc iodide in toluene under reflux for 4 days gave a 70% yield of triptycene monoquinone 4 (Scheme 14). Presumably, silver oxide oxidizes methoxyhydroquinone to methoxy-p-benzoquinone which undergoes Diels-Alder reaction with anthracene 2 to give adducts 5 (endo- and exo-isomers). Compound 5 then undergoes oxidation with silver oxide to give quinone 4. A catalytic amount of zinc iodide was added to facilitate the Diels-Alder reaction. No other regioisomers (such as isomers with methoxy substituent attached at C4a) were detected. To verify the reaction sequence, methoxyquinone 6, obtained from the oxidation of 3 with silver oxide and potassium carbonate in benzene (98% yield), was treated with anthracene 2 in toluene at 150° C. in a sealed tube to give adducts 5 (48% yield). Isomerization of ketones 5 with KOH in p-dioxane and water followed by oxidation with silver oxide gave monoquinone 4 (95% overall yield). Oxidation of monoquinone 4 with ceric ammonium nitrate afforded a 94% yield of triptycene bisquinone 7. Regioselective bromination of 7 was achieved by the treatment with N-bromosuccinimide (NBS) in DMF at 25° C. for 10 h to give bromoquinone 1 (45% yield). Alternatively, compound 1 can also be obtained from the bromination of monoquinone 4 with NBS in DMF at 40° C. followed by oxidation with ceric ammonium nitrate (59% overall yield). The bromination of quinones with NBS has not been reported previously, and apparently, reactivity of the methoxyquinone moiety towards NBS is greater than that of quinone and 1,4-dimethoxyphenyl moieties. Likely, the methoxy substituent of 7 or 4 (at C2) enhances nucleophilicity of adjacent double bond carbon resulting the bromination.

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

Procedure: In the reported synthesis of 5,8-disubstituted triptycene monoquinones, (Bartlett, P. D.; Ryan, M. J.; Cohen, S. G. J. Am. Chem. Soc. 1942, 64, 2649; Skvarehenko, V. R.; Shalaev, V. K.; Klabunovskii, E. I. Russ. Chem. Rev. 1974, 43, 951; Iwamura, H.; Maino, K. An intramolecular triptycene quinhydrone. J. Chem. Soc. Chem. Commun. 1978, 720.; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 1016-1038; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 2414; Patney, H. K. Synthesis 1991, 694. Charge-transfer complexes; Lipczynska-Kochany, E.; Iwamura, H. Chem. Lett. 1982, 1075; Daub, J.; Jakob, L.; Salbeck, J. Chem. Ber. 1988, 121, 2187. Radical Anions: Russell, G. A.; Suleman, N. K. J. Am. Chem. Soc. 1981, 103, 1560-1561. Liquid Crystals; Norvez, S. J. Org. Chem. 1993, 58, 2414) a sequence of three reactions was carried out: Diels-Alder reaction of 1,4-dimethoxyanthracene (Criswell, T. R.; Klanderman, B. H. J. Org. Chem. 1974, 39, 770) and p-benzoquinone followed by isomerization of the adducts (endo- and exo-adducts) with potassium hydroxide and then oxidation with silver oxide. These three reactions have been successfully combined into one simple operation. Hence, heating of anthracene 2 (derived from the reduction of 1,4-anthracenedione (Perchellet, E. M.; Magill, M. J.; Huang, X.; Brantis, C. E.; Hua, D. H.; Perchellet, J. P. Anti-cancer Drugs, 1999, 10, 749) with sodium hydrosulfite followed by sodium hydride and iodomethane), 1.4 equiv of methoxyhydroquinone (3), 2.7 equiv of silver oxide, and 0.2 equiv of zinc iodide in toluene under reflux for 4 days gave a 70% yield of triptycene monoquinone 4 (Scheme 14). Presumably, silver oxide oxidizes methoxyhydroquinone to methoxy-p-benzoquinone which undergoes Diels-Alder reaction with anthracene 2 to give adducts 5 (endo- and exo-isomers). Compound 5 then undergoes oxidation with silver oxide to give quinone 4. A catalytic amount of zinc iodide was added to facilitate the Diels-Alder reaction. No other regioisomers (such as isomers with methoxy substituent attached at C4a) were detected. To verify the reaction sequence, methoxyquinone 6, obtained from the oxidation of 3 with silver oxide and potassium carbonate in benzene (98% yield), was treated with anthracene 2 in toluene at 150° C. in a sealed tube to give adducts 5 (48% yield). Isomerization of ketones 5 with KOH in p-dioxane and water followed by oxidation with silver oxide gave monoquinone 4 (95% overall yield). Oxidation of monoquinone 4 with ceric ammonium nitrate afforded a 94% yield of triptycene bisquinone 7. Regioselective bromination of 7 was achieved by the treatment with N-bromosuccinimide (NBS) in DMF at 25° C. for 10 h to give bromoquinone 1 (45% yield). Alternatively, compound 1 can also be obtained from the bromination of monoquinone 4 with NBS in DMF at 40° C. followed by oxidation with ceric ammonium nitrate (59% overall yield). The bromination of quinones with NBS has not been reported previously, and apparently, reactivity of the methoxyquinone moiety towards NBS is greater than that of quinone and 1,4-dimethoxyphenyl moieties. Likely, the methoxy substituent of 7 or 4 (at C2) enhances nucleophilicity of adjacent double bond carbon resulting the bromination.

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

Procedure: In the reported synthesis of 5,8-disubstituted triptycene monoquinones, (Bartlett, P. D.; Ryan, M. J.; Cohen, S. G. J. Am. Chem. Soc. 1942, 64, 2649; Skvarehenko, V. R.; Shalaev, V. K.; Klabunovskii, E. I. Russ. Chem. Rev. 1974, 43, 951; Iwamura, H.; Maino, K. An intramolecular triptycene quinhydrone. J. Chem. Soc. Chem. Commun. 1978, 720.; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 1016-1038; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 2414; Patney, H. K. Synthesis 1991, 694. Charge-transfer complexes; Lipczynska-Kochany, E.; Iwamura, H. Chem. Lett. 1982, 1075; Daub, J.; Jakob, L.; Salbeck, J. Chem. Ber. 1988, 121, 2187. Radical Anions: Russell, G. A.; Suleman, N. K. J. Am. Chem. Soc. 1981, 103, 1560-1561. Liquid Crystals; Norvez, S. J. Org. Chem. 1993, 58, 2414) a sequence of three reactions was carried out: Diels-Alder reaction of 1,4-dimethoxyanthracene (Criswell, T. R.; Klanderman, B. H. J. Org. Chem. 1974, 39, 770) and p-benzoquinone followed by isomerization of the adducts (endo- and exo-adducts) with potassium hydroxide and then oxidation with silver oxide. These three reactions have been successfully combined into one simple operation. Hence, heating of anthracene 2 (derived from the reduction of 1,4-anthracenedione (Perchellet, E. M.; Magill, M. J.; Huang, X.; Brantis, C. E.; Hua, D. H.; Perchellet, J. P. Anti-cancer Drugs, 1999, 10, 749) with sodium hydrosulfite followed by sodium hydride and iodomethane), 1.4 equiv of methoxyhydroquinone (3), 2.7 equiv of silver oxide, and 0.2 equiv of zinc iodide in toluene under reflux for 4 days gave a 70% yield of triptycene monoquinone 4 (Scheme 14). Presumably, silver oxide oxidizes methoxyhydroquinone to methoxy-p-benzoquinone which undergoes Diels-Alder reaction with anthracene 2 to give adducts 5 (endo- and exo-isomers). Compound 5 then undergoes oxidation with silver oxide to give quinone 4. A catalytic amount of zinc iodide was added to facilitate the Diels-Alder reaction. No other regioisomers (such as isomers with methoxy substituent attached at C4a) were detected. To verify the reaction sequence, methoxyquinone 6, obtained from the oxidation of 3 with silver oxide and potassium carbonate in benzene (98% yield), was treated with anthracene 2 in toluene at 150° C. in a sealed tube to give adducts 5 (48% yield). Isomerization of ketones 5 with KOH in p-dioxane and water followed by oxidation with silver oxide gave monoquinone 4 (95% overall yield). Oxidation of monoquinone 4 with ceric ammonium nitrate afforded a 94% yield of triptycene bisquinone 7. Regioselective bromination of 7 was achieved by the treatment with N-bromosuccinimide (NBS) in DMF at 25° C. for 10 h to give bromoquinone 1 (45% yield). Alternatively, compound 1 can also be obtained from the bromination of monoquinone 4 with NBS in DMF at 40° C. followed by oxidation with ceric ammonium nitrate (59% overall yield). The bromination of quinones with NBS has not been reported previously, and apparently, reactivity of the methoxyquinone moiety towards NBS is greater than that of quinone and 1,4-dimethoxyphenyl moieties. Likely, the methoxy substituent of 7 or 4 (at C2) enhances nucleophilicity of adjacent double bond carbon resulting the bromination.

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

Procedure: In the reported synthesis of 5,8-disubstituted triptycene monoquinones, (Bartlett, P. D.; Ryan, M. J.; Cohen, S. G. J. Am. Chem. Soc. 1942, 64, 2649; Skvarehenko, V. R.; Shalaev, V. K.; Klabunovskii, E. I. Russ. Chem. Rev. 1974, 43, 951; Iwamura, H.; Maino, K. An intramolecular triptycene quinhydrone. J. Chem. Soc. Chem. Commun. 1978, 720.; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 1016-1038; Quast, H.; Fuchsbauer, H. -L. Chem. Ber. 1986, 119, 2414; Patney, H. K. Synthesis 1991, 694. Charge-transfer complexes; Lipczynska-Kochany, E.; Iwamura, H. Chem. Lett. 1982, 1075; Daub, J.; Jakob, L.; Salbeck, J. Chem. Ber. 1988, 121, 2187. Radical Anions: Russell, G. A.; Suleman, N. K. J. Am. Chem. Soc. 1981, 103, 1560-1561. Liquid Crystals; Norvez, S. J. Org. Chem. 1993, 58, 2414) a sequence of three reactions was carried out: Diels-Alder reaction of 1,4-dimethoxyanthracene (Criswell, T. R.; Klanderman, B. H. J. Org. Chem. 1974, 39, 770) and p-benzoquinone followed by isomerization of the adducts (endo- and exo-adducts) with potassium hydroxide and then oxidation with silver oxide. These three reactions have been successfully combined into one simple operation. Hence, heating of anthracene 2 (derived from the reduction of 1,4-anthracenedione (Perchellet, E. M.; Magill, M. J.; Huang, X.; Brantis, C. E.; Hua, D. H.; Perchellet, J. P. Anti-cancer Drugs, 1999, 10, 749) with sodium hydrosulfite followed by sodium hydride and iodomethane), 1.4 equiv of methoxyhydroquinone (3), 2.7 equiv of silver oxide, and 0.2 equiv of zinc iodide in toluene under reflux for 4 days gave a 70% yield of triptycene monoquinone 4 (Scheme 14). Presumably, silver oxide oxidizes methoxyhydroquinone to methoxy-p-benzoquinone which undergoes Diels-Alder reaction with anthracene 2 to give adducts 5 (endo- and exo-isomers). Compound 5 then undergoes oxidation with silver oxide to give quinone 4. A catalytic amount of zinc iodide was added to facilitate the Diels-Alder reaction. No other regioisomers (such as isomers with methoxy substituent attached at C4a) were detected. To verify the reaction sequence, methoxyquinone 6, obtained from the oxidation of 3 with silver oxide and potassium carbonate in benzene (98% yield), was treated with anthracene 2 in toluene at 150° C. in a sealed tube to give adducts 5 (48% yield). Isomerization of ketones 5 with KOH in p-dioxane and water followed by oxidation with silver oxide gave monoquinone 4 (95% overall yield). Oxidation of monoquinone 4 with ceric ammonium nitrate afforded a 94% yield of triptycene bisquinone 7. Regioselective bromination of 7 was achieved by the treatment with N-bromosuccinimide (NBS) in DMF at 25° C. for 10 h to give bromoquinone 1 (45% yield). Alternatively, compound 1 can also be obtained from the bromination of monoquinone 4 with NBS in DMF at 40° C. followed by oxidation with ceric ammonium nitrate (59% overall yield). The bromination of quinones with NBS has not been reported previously, and apparently, reactivity of the methoxyquinone moiety towards NBS is greater than that of quinone and 1,4-dimethoxyphenyl moieties. Likely, the methoxy substituent of 7 or 4 (at C2) enhances nucleophilicity of adjacent double bond carbon resulting the bromination.

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

Procedure: To a 250 ml-round-bottom flask, was added 2 g (MW 208; 0.0096 mol) of 1,4-anthracenedione (4). To it a solution of 6.6816 g (MW 174; 0.0384 mol) of sodium hydrosulfite in 50 mL of distilled water and 50 mL of 1,4-dioxane were added. The resulting mixture was stirred at room temperature for 2-3 hours. The reaction progress is checked with TLC (using CH2Cl2:hexanes:ether 1:1:0.2 as the eluant). The mixture was transferred to a 500-mL beaker slowly, cooled over an ice-water bath, and added 100 mL of distilled water. Dark green solids precipitated. The beaker was covered with aluminum foil, and placed in the refrigerator for 1 h. The solid was filtered through a glass fritted funnel and the product was washed with 30 mL of distilled water twice. The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.; 1H NMR (CDCl3 contains a small amount of p-dioxane) d 8.7 (m, 2H, C 9,10 Hs), 8.05 (m, 2H, C 5,8 Hs), 7.5 (s, 2H, C 6,7 Hs), 6.6 (s, 2H, C 2,3 Hs). The diol is insoluble in chloroform but soluble in DMSO and DMF. cooled over an ice-water bath Dark green solids precipitated placed in the refrigerator for 1 h The solid was filtered through a glass fritted funnel the product was washed with 30 mL of distilled water twice The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.

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

Procedure: To a 250 ml-round-bottom flask, was added 2 g (MW 208; 0.0096 mol) of 1,4-anthracenedione (4). To it a solution of 6.6816 g (MW 174; 0.0384 mol) of sodium hydrosulfite in 50 mL of distilled water and 50 mL of 1,4-dioxane were added. The resulting mixture was stirred at room temperature for 2-3 hours. The reaction progress is checked with TLC (using CH2Cl2:hexanes:ether 1:1:0.2 as the eluant). The mixture was transferred to a 500-mL beaker slowly, cooled over an ice-water bath, and added 100 mL of distilled water. Dark green solids precipitated. The beaker was covered with aluminum foil, and placed in the refrigerator for 1 h. The solid was filtered through a glass fritted funnel and the product was washed with 30 mL of distilled water twice. The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.; 1H NMR (CDCl3 contains a small amount of p-dioxane) d 8.7 (m, 2H, C 9,10 Hs), 8.05 (m, 2H, C 5,8 Hs), 7.5 (s, 2H, C 6,7 Hs), 6.6 (s, 2H, C 2,3 Hs). The diol is insoluble in chloroform but soluble in DMSO and DMF. cooled over an ice-water bath Dark green solids precipitated placed in the refrigerator for 1 h The solid was filtered through a glass fritted funnel the product was washed with 30 mL of distilled water twice The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.

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

Procedure: To a 250 ml-round-bottom flask, was added 2 g (MW 208; 0.0096 mol) of 1,4-anthracenedione (4). To it a solution of 6.6816 g (MW 174; 0.0384 mol) of sodium hydrosulfite in 50 mL of distilled water and 50 mL of 1,4-dioxane were added. The resulting mixture was stirred at room temperature for 2-3 hours. The reaction progress is checked with TLC (using CH2Cl2:hexanes:ether 1:1:0.2 as the eluant). The mixture was transferred to a 500-mL beaker slowly, cooled over an ice-water bath, and added 100 mL of distilled water. Dark green solids precipitated. The beaker was covered with aluminum foil, and placed in the refrigerator for 1 h. The solid was filtered through a glass fritted funnel and the product was washed with 30 mL of distilled water twice. The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.; 1H NMR (CDCl3 contains a small amount of p-dioxane) d 8.7 (m, 2H, C 9,10 Hs), 8.05 (m, 2H, C 5,8 Hs), 7.5 (s, 2H, C 6,7 Hs), 6.6 (s, 2H, C 2,3 Hs). The diol is insoluble in chloroform but soluble in DMSO and DMF. cooled over an ice-water bath Dark green solids precipitated placed in the refrigerator for 1 h The solid was filtered through a glass fritted funnel the product was washed with 30 mL of distilled water twice The solid product was dried under vacuum to give 1.754 g (87% yield), mp 167-169° C.

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

Procedure: A solution of sodium hydrosulfite (16.70 g, 42.0 mmol, 1 molar equivalent) in a water/dioxane (3/2) (250 mL) mixture is added under nitrogen to the 1,4-anthracenedione 1a (5.00 g, 24.0 mmol, 1 molar equivalent). The resulting mixture is stirred at room temperature for 3 h. Water is added and the resulting precipitate is filtered, washed with water and dried under vacuum to give the title compound as a yellow powder (3.10 g, 61%). 1H NMR (300.13 MHz, THF-d8) (ppm) 6.53 (s, 2H) 7.34-7.40 (m, 2H) 7.96-7.99 (m, 2H) 8.65 (s, 2H) 8.70 (s, 2H). the resulting precipitate is filtered washed with water dried under vacuum