3,6-dimethylbenzene-1,2-diol

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

Procedure: Mixtures of 4-hydroxyindole (0.1-10%) and 5-hydroxyindole (0.1-10%), 6-hydroxyindole (0.1-10%), or 7-hydroxyindole (0.1-10%) will give a color range from black to light auburn. 5-Hydroxyindole (0.1-10%) was found to produce progressively darker browns and, eventually, black through the addition of 3-methylcatechol (0.1-10%), 3-methoxycatechol (0.1-10%), or 3,6-dimethylcatechol (0.1-10%) followed by oxidation by sodium periodate (15%). 4-Hydroxyindole (1%) was found to produce progressively lighter colors with increasing red highlights through the addition of dopamine (2-5%) when penetration of precursors was done at high pH (9.2). Therefore a range of colors from light brown to black can be obtained through combinations of 4-hydroxyindole, 5-hydroxyindole, 6-hydroxyindole, and 7-hydroxyindole with each other or various other dye precursors. Similar results were obtained in staining skin in that a range of shades from light to dark brown can be obtained through combinations of hydroxyindoles with various other dye precursors. to produce progressively darker browns to produce progressively lighter colors with increasing red highlights

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

Procedure: Mixtures of 4-hydroxyindole (0.1-10%) and 5-hydroxyindole (0.1-10%), 6-hydroxyindole (0.1-10%), or 7-hydroxyindole (0.1-10%) will give a color range from black to light auburn. 5-Hydroxyindole (0.1-10%) was found to produce progressively darker browns and, eventually, black through the addition of 3-methylcatechol (0.1-10%), 3-methoxycatechol (0.1-10%), or 3,6-dimethylcatechol (0.1-10%) followed by oxidation by sodium periodate (15%). 4-Hydroxyindole (1%) was found to produce progressively lighter colors with increasing red highlights through the addition of dopamine (2-5%) when penetration of precursors was done at high pH (9.2). Therefore a range of colors from light brown to black can be obtained through combinations of 4-hydroxyindole, 5-hydroxyindole, 6-hydroxyindole, and 7-hydroxyindole with each other or various other dye precursors. Similar results were obtained in staining skin in that a range of shades from light to dark brown can be obtained through combinations of hydroxyindoles with various other dye precursors. to produce progressively darker browns to produce progressively lighter colors with increasing red highlights

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

Procedure: To 0.03 mol 1,4-xylenediol were added 30 ml tetrahydrofuran and 0.09 mol pyridine, then added 0.075 mol benzoyl chloride with stirring. The reaction was heated refluxing for 4 hours, cooled and added 20 ml saturated saline. The reaction mixture was extracted with ethyl acetate, and the extract was dried over anhydrous sodium sulfate, filtered. After removing solvent, the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1, v/v) to give 1,4-xylenediol dibenzoate as a white solid, and the yield was 95%, mp was 84-85° C. 1HNMR: δ (ppm) 5.3(4H, s, CH2 linked to ester radical), 7.4-8.1(10H, m, ArH) The reaction was heated refluxing for 4 hours cooled added 20 ml saturated saline The reaction mixture was extracted with ethyl acetate the extract was dried over anhydrous sodium sulfate filtered After removing solvent the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1

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

Procedure: To 0.03 mol 1,4-xylenediol were added 30 ml tetrahydrofuran and 0.09 mol pyridine, then added 0.075 mol benzoyl chloride with stirring. The reaction was heated refluxing for 4 hours, cooled and added 20 ml saturated saline. The reaction mixture was extracted with ethyl acetate, and the extract was dried over anhydrous sodium sulfate, filtered. After removing solvent, the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1, v/v) to give 1,4-xylenediol dibenzoate as a white solid, and the yield was 95%, mp was 84-85° C. 1HNMR: δ (ppm) 5.3(4H, s, CH2 linked to ester radical), 7.4-8.1(10H, m, ArH) The reaction was heated refluxing for 4 hours cooled added 20 ml saturated saline The reaction mixture was extracted with ethyl acetate the extract was dried over anhydrous sodium sulfate filtered After removing solvent the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5,8-Dimethyl-1,4-benzodioxane. To a stirred solution of 3 g of 3,6-dimethylcatechol and 6.15 g of potassium carbonate in 35 mL of ethylene glycol is added 3.74 mL of dibromoethane. A reflux condenser is attached and the mixture heated in an oil bath to 120° C. for 4 hours. The mixture is allowed to cool to room temperature and then is distributed between 100 mL of saturated potassium carbonate solution and 200 mL of ether. The ether layer is dried over magnesium sulfate and concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel to afford 2.90 g of 5,8-dimethyl-1,3-benzodioxane as a light yellow liquid. A reflux condenser is attached to cool to room temperature The ether layer is dried over magnesium sulfate concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel

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

Procedure: By following in the same manner as in Example 53, except that 100 g. (819 m. moles) of 2,5-dimethylphenol were used instead of 3,5-dimethylphenol, 1.45 g. (10.5 m. moles) of 3,6-dimethylcatechol and 1.85 g. (13.4 m. moles) of 2,5-dimethylhydroquinone were obtained. The yield of dihydric alkylphenols was 46.9 percent.

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5,8-Dimethyl-1,4-benzodioxane. To a stirred solution of 3 g of 3,6-dimethylcatechol and 6.15 g of potassium carbonate in 35 mL of ethylene glycol is added 3.74 mL of dibromoethane. A reflux condenser is attached and the mixture heated in an oil bath to 120° C. for 4 hours. The mixture is allowed to cool to room temperature and then is distributed between 100 mL of saturated potassium carbonate solution and 200 mL of ether. The ether layer is dried over magnesium sulfate and concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel to afford 2.90 g of 5,8-dimethyl-1,3-benzodioxane as a light yellow liquid. A reflux condenser is attached to cool to room temperature The ether layer is dried over magnesium sulfate concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 2.97 g of 3,6-dimethylcatechol and 3.86 g of potassium carbonate in 60 mL of N,N-dimethylformamide is added 1.69 mL of bromochloromethane. A reflux condenser is attached and the mixture heated in an oil bath to 100° C. for 24 hours. The mixture is allowed to cool to room temperature and then is distributed between 100 mL of water and 200 mL of ether. The aqueous layer is separated and extracted with ether. The combined ether layers are dried over magnesium sulfate and concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel to afford 2.0 g of 4,7-dimethyl-1,3-benzodioxole as a light yellow liquid. A reflux condenser is attached to cool to room temperature The aqueous layer is separated extracted with ether The combined ether layers are dried over magnesium sulfate concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 3.00 g of 3,6-dimethylcatechol and 6.15 g of potassium carbonate in 35 mL of ethylene glycol is added 3.74 mL of dibromoethane. A reflux condenser is attached and the mixture heated in an oil bath to 120° C. for 4 hours. The mixture is allowed to cool to room temperature and then is distributed between 100 mL of saturated potassium carbonate solution and 200 mL of ether. The ether layer is dried over magnesium sulfate and concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel to afford 2.90 g of 5,8-dimethyl-1,3-benzodioxane as a light yellow liquid. A reflux condenser is attached to cool to room temperature The ether layer is dried over magnesium sulfate concentrated under reduced pressure to yield a red liquid, which is purified by chromatography on silica gel

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

Procedure: Mixtures of 4-hydroxyindole (0.1-10%) and 5-hydroxyindole (0.1-10%), 6-hydroxyindole (0.1-10%), or 7-hydroxyindole (0.1-10%) will give a color range from black to light auburn. 5-Hydroxyindole (0.1-10%) was found to produce progressively darker browns and, eventually, black through the addition of 3-methylcatechol (0.1-10%), 3-methoxycatechol (0.1-10%), or 3,6-dimethylcatechol (0.1-10%) followed by oxidation by sodium periodate (15%). 4-Hydroxyindole (1%) was found to produce progressively lighter colors with increasing red highlights through the addition of dopamine (2-5%) when penetration of precursors was done at high pH (9.2). Therefore a range of colors from light brown to black can be obtained through combinations of 4-hydroxyindole, 5-hydroxyindole, 6-hydroxyindole, and 7-hydroxyindole with each other or various other dye precursors. Similar results were obtained in staining skin in that a range of shades from light to dark brown can be obtained through combinations of hydroxyindoles with various other dye precursors. to produce progressively darker browns to produce progressively lighter colors with increasing red highlights

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

Procedure: To 0.03 mol 1,4-xylenediol were added 30 ml tetrahydrofuran and 0.09 mol pyridine, then added 0.075 mol benzoyl chloride with stirring. The reaction was heated refluxing for 4 hours, cooled and added 20 ml saturated saline. The reaction mixture was extracted with ethyl acetate, and the extract was dried over anhydrous sodium sulfate, filtered. After removing solvent, the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1, v/v) to give 1,4-xylenediol dibenzoate as a white solid, and the yield was 95%, mp was 84-85° C. 1HNMR: δ (ppm) 5.3(4H, s, CH2 linked to ester radical), 7.4-8.1(10H, m, ArH) The reaction was heated refluxing for 4 hours cooled added 20 ml saturated saline The reaction mixture was extracted with ethyl acetate the extract was dried over anhydrous sodium sulfate filtered After removing solvent the crude was purified by recrystallization from ethyl acetate and petroleum ether (1:1