2,4-dimethoxynaphthalen-1-ol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran was added 0.694 g of methyl chloroformate followed by 0.743 g of triethylamine. The mixture was stirred at room temperature for 16 hours, filtered, then the solvent removed under reduced pressure. The residue was dissolved in diethyl ether, washed with dilute hydrochloric acid and dried over anhydrous sodium sulfate. The ether was removed under reduced pressure and the residue chromatographed on silica gel, eluting with a 1:1 mixture of methylene chloride and hexane, to give 1-methoxycarbonyloxy-2,4-dimethoxynaphthalene, m.p. 128°-129° C. filtered the solvent removed under reduced pressure The residue was dissolved in diethyl ether washed with dilute hydrochloric acid dried over anhydrous sodium sulfate The ether was removed under reduced pressure the residue chromatographed on silica gel eluting with a 1:1 mixture of methylene chloride and hexane

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

Procedure: To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran and 1 ml of pyridine is added 10 ml of a solution of 12.5% phosgene in benzene. The mixture is stirred overnight at 25° C., filtered and the filtrate evaporated under vacuum to afford crude 1-chlorocarbonyloxy-2,4-dimethoxynaphthalene. This chloroformate is dissolved in 50 ml of dry tetrahydrofuran and a solution of 1.14 g of diethylamine in 10 ml of tetrahydrofuran added. After 4 hours at room temperature the reaction mixture is diluted with ethyl acetate and washed with dilute hydrochloric acid. The organic phase is dried over sodium sulfate and solvent removed under reduced pressure to yield 1-diethylcarbamoyloxy-2,4-dimethoxynaphthalene. filtered the filtrate evaporated under vacuum

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

Procedure: To a solution of 1.00 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran was added 0.335 g of methyl isocyanate followed by 0.12 g of 4-dimethylaminopyridine. The solution was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue dissolved in ethyl acetate, washed with dilute hydrochloric acid and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the residue chromatographed on silica gel, eluting with methylene chloride, giving 1-methylcarbamoyloxy-2,4-dimethoxynaphthalene, m.p. 131°-133° C. The solvent was removed under reduced pressure the residue dissolved in ethyl acetate washed with dilute hydrochloric acid dried over anhydrous sodium sulfate The solvent was removed under reduced pressure the residue chromatographed on silica gel eluting with methylene chloride

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

Procedure: To a solution of 1.00 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran was added 0.335 g of methyl isocyanate followed by 0.12 g of 4-dimethylaminopyridine. The solution was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue dissolved in ethyl acetate, washed with dilute hydrochloric acid and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the residue chromatographed on silica gel, eluting with methylene chloride, giving 1-methylcarbamoyloxy-2,4-dimethoxynaphthalene, m.p. 131°-133° C. The solvent was removed under reduced pressure the residue dissolved in ethyl acetate washed with dilute hydrochloric acid dried over anhydrous sodium sulfate The solvent was removed under reduced pressure the residue chromatographed on silica gel eluting with methylene chloride

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

Procedure: A solution of 18.9 g of 2-methoxynaphthoquinone in methanol was added slowly to a solution of 34.8 g of sodium hydrosulfite in methanol and the mixture stirred for 1 hour. The solvent was removed under reduced pressure and the residue partitioned between ethyl acetate and water. The organic layer was dried over anhydrous sodium sulfate and evaporated to a purple solid. The solid was dissolved in 200 ml of methanol previously saturated with anhydrous hydrochloric acid and stirred for 3 minutes at 60° C. The mixture was then diluted with 200 ml of ice water and the precipitate filtered off, dried under vacuum and recrystallized from ether/pentane to give 13.25 g of 1-hydroxy-2,4-dimethoxynaphthalene, m.p. 87°-88° C. The solvent was removed under reduced pressure the residue partitioned between ethyl acetate and water The organic layer was dried over anhydrous sodium sulfate evaporated to a purple solid The solid was dissolved in 200 ml of methanol previously saturated with anhydrous hydrochloric acid stirred for 3 minutes at 60° C The mixture was then diluted with 200 ml of ice water the precipitate filtered off dried under vacuum recrystallized from ether/pentane

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

Procedure: To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran was added 0.694 g of methyl chloroformate followed by 0.743 g of triethylamine. The mixture was stirred at room temperature for 16 hours, filtered, then the solvent removed under reduced pressure. The residue was dissolved in diethyl ether, washed with dilute hydrochloric acid and dried over anhydrous sodium sulfate. The ether was removed under reduced pressure and the residue chromatographed on silica gel, eluting with a 1:1 mixture of methylene chloride and hexane, to give 1-methoxycarbonyloxy-2,4-dimethoxynaphthalene, m.p. 128°-129° C. filtered the solvent removed under reduced pressure The residue was dissolved in diethyl ether washed with dilute hydrochloric acid dried over anhydrous sodium sulfate The ether was removed under reduced pressure the residue chromatographed on silica gel eluting with a 1:1 mixture of methylene chloride and hexane

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

Procedure: To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran and 1 ml of pyridine is added 10 ml of a solution of 12.5% phosgene in benzene. The mixture is stirred overnight at 25° C., filtered and the filtrate evaporated under vacuum to afford crude 1-chlorocarbonyloxy-2,4-dimethoxynaphthalene. This chloroformate is dissolved in 50 ml of dry tetrahydrofuran and a solution of 1.14 g of diethylamine in 10 ml of tetrahydrofuran added. After 4 hours at room temperature the reaction mixture is diluted with ethyl acetate and washed with dilute hydrochloric acid. The organic phase is dried over sodium sulfate and solvent removed under reduced pressure to yield 1-diethylcarbamoyloxy-2,4-dimethoxynaphthalene. filtered the filtrate evaporated under vacuum

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

Procedure: To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran and 1 ml of pyridine is added 10 ml of a solution of 12.5% phosgene in benzene. The mixture is stirred overnight at 25° C., filtered and the filtrate evaporated under vacuum to afford crude 1-chlorocarbonyloxy-2,4-dimethoxynaphthalene. This chloroformate is dissolved in 50 ml of dry tetrahydrofuran and a solution of 1.14 g of diethylamine in 10 ml of tetrahydrofuran added. After 4 hours at room temperature the reaction mixture is diluted with ethyl acetate and washed with dilute hydrochloric acid. The organic phase is dried over sodium sulfate and solvent removed under reduced pressure to yield 1-diethylcarbamoyloxy-2,4-dimethoxynaphthalene. filtered the filtrate evaporated under vacuum

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

Procedure: To a solution of 1.00 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran was added 0.335 g of methyl isocyanate followed by 0.12 g of 4-dimethylaminopyridine. The solution was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue dissolved in ethyl acetate, washed with dilute hydrochloric acid and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the residue chromatographed on silica gel, eluting with methylene chloride, giving 1-methylcarbamoyloxy-2,4-dimethoxynaphthalene, m.p. 131°-133° C. The solvent was removed under reduced pressure the residue dissolved in ethyl acetate washed with dilute hydrochloric acid dried over anhydrous sodium sulfate The solvent was removed under reduced pressure the residue chromatographed on silica gel eluting with methylene chloride

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

Procedure: A solution of 18.9 g of 2-methoxynaphthoquinone in methanol was added slowly to a solution of 34.8 g of sodium hydrosulfite in methanol and the mixture stirred for 1 hour. The solvent was removed under reduced pressure and the residue partitioned between ethyl acetate and water. The organic layer was dried over anhydrous sodium sulfate and evaporated to a purple solid. The solid was dissolved in 200 ml of methanol previously saturated with anhydrous hydrochloric acid and stirred for 3 minutes at 60° C. The mixture was then diluted with 200 ml of ice water and the precipitate filtered off, dried under vacuum and recrystallized from ether/pentane to give 13.25 g of 1-hydroxy-2,4-dimethoxynaphthalene, m.p. 87°-88° C. The solvent was removed under reduced pressure the residue partitioned between ethyl acetate and water The organic layer was dried over anhydrous sodium sulfate evaporated to a purple solid The solid was dissolved in 200 ml of methanol previously saturated with anhydrous hydrochloric acid stirred for 3 minutes at 60° C The mixture was then diluted with 200 ml of ice water the precipitate filtered off dried under vacuum recrystallized from ether/pentane