ethyl 4-phenoxybutanoate

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

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

Procedure: To potassium tert-butoxide (1.35 g, 12 mmol) in tetrahydrofuran (30 mL) was added diethyl oxalate (2.2 g, 15 mmol) and ethyl 4-phenoxybutanoate (2.08 g, 10 mmol) in tetrahydrofuran (30 mL) at 0° C. dropwise. The mixture was allowed to stir overnight, concentrated, quenched with 1 N HCl(aq), extracted with ethyl acetate, and concentrated. A fraction of this material (308 mg, 1 mmol) was added to concentrated H2SO4 at 0° C. The mixture was stirred for 1.5 hours and was poured onto ice chips. The precipitate was collected to afford the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 8.44 (dd, J=1.5, 8.1 Hz, 1H), 7.48 (t, J=8.1 Hz, 1H), 7.25 (t, J=7.8 Hz, 1H), 7.14 (d, J=8.4 Hz, 1H), 4.28 (t, J=5.1 Hz, 2H), and 3.02 (t, J=5.1 Hz, 2H). concentrated quenched with 1 N HCl(aq) extracted with ethyl acetate concentrated The mixture was stirred for 1.5 hours was poured onto ice chips The precipitate was collected

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

Procedure: To potassium tert-butoxide (1.35 g, 12 mmol) in tetrahydrofuran (30 mL) was added diethyl oxalate (2.2 g, 15 mmol) and ethyl 4-phenoxybutanoate (2.08 g, 10 mmol) in tetrahydrofuran (30 mL) at 0° C. dropwise. The mixture was allowed to stir overnight, concentrated, quenched with 1 N HCl(aq), extracted with ethyl acetate, and concentrated. A fraction of this material (308 mg, 1 mmol) was added to concentrated H2SO4 at 0° C. The mixture was stirred for 1.5 hours and was poured onto ice chips. The precipitate was collected to afford the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 8.44 (dd, J=1.5, 8.1 Hz, 1H), 7.48 (t, J=8.1 Hz, 1H), 7.25 (t, J=7.8 Hz, 1H), 7.14 (d, J=8.4 Hz, 1H), 4.28 (t, J=5.1 Hz, 2H), and 3.02 (t, J=5.1 Hz, 2H). concentrated quenched with 1 N HCl(aq) extracted with ethyl acetate concentrated The mixture was stirred for 1.5 hours was poured onto ice chips The precipitate was collected

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

Procedure: To a solution of phenol (3.16 g, 33.6 mmol) in acetonitrile, was added ethyl 4-bromobutyrate (4.8 ml, 33.6 mmol), potassium carbonate (4.64 g, 33.6 mmol) and tetrabutylammonium iodide (370 mg, 1 mmol). The reaction mixture was stirred vigorously and heated to reflux for 2 days before being cooled, filtered, dried (MgSO4) and concentrated in-vacuo to yield 4-phenoxy-butyric acid ethyl ester. 4-Phenoxy-butyric acid ethyl ester was hydrolyzed to its corresponding carboxylic acid using sodium hydroxide mediated hydrolysis to yield 4-phenoxy-butyric acid. To a solution of 4-phenoxy-butyric acid (7.67 g, 29.6 mmol) in anhydrous dichloromethane was added oxalyl chloride (4.4 ml, 50.3 mmol) and one drop of dimethyl formamide and the reaction mixture stirred at room temperature for 30 minutes. Reaction mixture was concentrated in-vacuo and the residue dissolved in 1,2-dichloroethane (90 ml). This solution was added drop wise to a suspension of aluminum trichloride (4.73 g, 35.5 mmol) in 1,2-dichloroethane (50 ml) at 0° C. Reaction mixture was left stirring in ice bath which rose to room temperature overnight. The reaction mixture was poured over conc. hydrochloric acid (30 ml) stirred into 100 g ice, and then stirred for a further 90 minutes until the ice fully melted. The aqueous phase was washed with dichloromethane 3 times, before the organics were combined, dried (Na2SO4) and concentrated in-vacuo. Purification by triturating with diethyl ether gave 3,4-dihydro-2H-benzo[b]oxepin-5-one.

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

Procedure: To a solution of phenol (3.16 g, 33.6 mmol) in acetonitrile, was added ethyl 4-bromobutyrate (4.8 ml, 33.6 mmol), potassium carbonate (4.64 g, 33.6 mmol) and tetrabutylammonium iodide (370 mg, 1 mmol). The reaction mixture was stirred vigorously and heated to reflux for 2 days before being cooled, filtered, dried (MgSO4) and concentrated in-vacuo to yield 4-phenoxy-butyric acid ethyl ester. 4-Phenoxy-butyric acid ethyl ester was hydrolyzed to its corresponding carboxylic acid using sodium hydroxide mediated hydrolysis to yield 4-phenoxy-butyric acid. To a solution of 4-phenoxy-butyric acid (7.67 g, 29.6 mmol) in anhydrous dichloromethane was added oxalyl chloride (4.4 ml, 50.3 mmol) and one drop of dimethyl formamide and the reaction mixture stirred at room temperature for 30 minutes. Reaction mixture was concentrated in-vacuo and the residue dissolved in 1,2-dichloroethane (90 ml). This solution was added drop wise to a suspension of aluminum trichloride (4.73 g, 35.5 mmol) in 1,2-dichloroethane (50 ml) at 0° C. Reaction mixture was left stirring in ice bath which rose to room temperature overnight. The reaction mixture was poured over conc. hydrochloric acid (30 ml) stirred into 100 g ice, and then stirred for a further 90 minutes until the ice fully melted. The aqueous phase was washed with dichloromethane 3 times, before the organics were combined, dried (Na2SO4) and concentrated in-vacuo. Purification by triturating with diethyl ether gave 3,4-dihydro-2H-benzo[b]oxepin-5-one. heated to reflux for 2 days before being cooled filtered dried (MgSO4) concentrated in-vacuo

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

Procedure: To a solution of phenol (3.16 g, 33.6 mmol) in acetonitrile, was added ethyl 4-bromobutyrate (4.8 ml, 33.6 mmol), potassium carbonate (4.64 g, 33.6 mmol) and tetrabutylammonium iodide (370 mg, 1 mmol). The reaction mixture was stirred vigorously and heated to reflux for 2 days before being cooled, filtered, dried (MgSO4) and concentrated in-vacuo to yield 4-phenoxy-butyric acid ethyl ester. 4-Phenoxy-butyric acid ethyl ester was hydrolyzed to its corresponding carboxylic acid using sodium hydroxide mediated hydrolysis to yield 4-phenoxy-butyric acid. To a solution of 4-phenoxy-butyric acid (7.67 g, 29.6 mmol) in anhydrous dichloromethane was added oxalyl chloride (4.4 ml, 50.3 mmol) and one drop of dimethyl formamide and the reaction mixture stirred at room temperature for 30 minutes. Reaction mixture was concentrated in-vacuo and the residue dissolved in 1,2-dichloroethane (90 ml). This solution was added drop wise to a suspension of aluminum trichloride (4.73 g, 35.5 mmol) in 1,2-dichloroethane (50 ml) at 0° C. Reaction mixture was left stirring in ice bath which rose to room temperature overnight. The reaction mixture was poured over conc. hydrochloric acid (30 ml) stirred into 100 g ice, and then stirred for a further 90 minutes until the ice fully melted. The aqueous phase was washed with dichloromethane 3 times, before the organics were combined, dried (Na2SO4) and concentrated in-vacuo. Purification by triturating with diethyl ether gave 3,4-dihydro-2H-benzo[b]oxepin-5-one. heated to reflux for 2 days before being cooled filtered dried (MgSO4) concentrated in-vacuo

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

Procedure: Scheme 1 shows a general method for preparation of 3,4-dihydrobenzo[b]oxepin-5(2H)-one intermediates 66 by O-alkylation of a phenolic compound with ethyl 4-bromobutanoate to give a ethyl 4-phenoxybutanoate intermediate 67, followed by saponification to the carboxylic acid 68 and intramolecular cyclization under acidic conditions.

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

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

Procedure: Scheme 1 shows a general method for preparation of 3,4-dihydrobenzo[b]oxepin-5(2H)-one intermediates 66 by O-alkylation of a phenolic compound with ethyl 4-bromobutanoate to give a ethyl 4-phenoxybutanoate intermediate 67, followed by saponification to the carboxylic acid 68 and intramolecular cyclization under acidic conditions.

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

Procedure: To a solution of phenol (3.16 g, 33.6 mmol) in acetonitrile, was added ethyl 4-bromobutyrate (4.8 ml, 33.6 mmol), potassium carbonate (4.64 g, 33.6 mmol) and tetrabutylammonium iodide (370 mg, 1 mmol). The reaction mixture was stirred vigorously and heated to reflux for 2 days before being cooled, filtered, dried (MgSO4) and concentrated in-vacuo to yield 4-phenoxy-butyric acid ethyl ester. 4-Phenoxy-butyric acid ethyl ester was hydrolyzed to its corresponding carboxylic acid using sodium hydroxide mediated hydrolysis to yield 4-phenoxy-butyric acid. To a solution of 4-phenoxy-butyric acid (7.67 g, 29.6 mmol) in anhydrous dichloromethane was added oxalyl chloride (4.4 ml, 50.3 mmol) and one drop of dimethyl formamide and the reaction mixture stirred at room temperature for 30 minutes. Reaction mixture was concentrated in-vacuo and the residue dissolved in 1,2-dichloroethane (90 ml). This solution was added drop wise to a suspension of aluminum trichloride (4.73 g, 35. 5 mmol) in 1,2-dichloroethane (50 ml) at 0° C. Reaction mixture was left stirring in ice bath which rose to room temperature overnight. The reaction mixture was poured over conc. hydrochloric acid (30 ml) stirred into 10 0 g ice, and then stirred for a further 90 minutes until the ice fully melted. The aqueous phase was washed with dichloromethane 3 times, before the organics were combined, dried (Na2SO4) and concentrated in-vacuo. Purification by triturating with diethylether gave 3,4-dihydro-2H-benzo[b]oxepin-5-one.

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

Procedure: To a solution of phenol (3.16 g, 33.6 mmol) in acetonitrile, was added ethyl 4-bromobutyrate (4.8 ml, 33.6 mmol), potassium carbonate (4.64 g, 33.6 mmol) and tetrabutylammonium iodide (370 mg, 1 mmol). The reaction mixture was stirred vigorously and heated to reflux for 2 days before being cooled, filtered, dried (MgSO4) and concentrated in-vacuo to yield 4-phenoxy-butyric acid ethyl ester. 4-Phenoxy-butyric acid ethyl ester was hydrolyzed to its corresponding carboxylic acid using sodium hydroxide mediated hydrolysis to yield 4-phenoxy-butyric acid. To a solution of 4-phenoxy-butyric acid (7.67 g, 29.6 mmol) in anhydrous dichloromethane was added oxalyl chloride (4.4 ml, 50.3 mmol) and one drop of dimethyl formamide and the reaction mixture stirred at room temperature for 30 minutes. Reaction mixture was concentrated in-vacuo and the residue dissolved in 1,2-dichloroethane (90 ml). This solution was added drop wise to a suspension of aluminum trichloride (4.73 g, 35. 5 mmol) in 1,2-dichloroethane (50 ml) at 0° C. Reaction mixture was left stirring in ice bath which rose to room temperature overnight. The reaction mixture was poured over conc. hydrochloric acid (30 ml) stirred into 10 0 g ice, and then stirred for a further 90 minutes until the ice fully melted. The aqueous phase was washed with dichloromethane 3 times, before the organics were combined, dried (Na2SO4) and concentrated in-vacuo. Purification by triturating with diethylether gave 3,4-dihydro-2H-benzo[b]oxepin-5-one. heated to reflux for 2 days before being cooled filtered dried (MgSO4) concentrated in-vacuo

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

Procedure: To potassium tert-butoxide (1.35 g, 12 mmol) in tetrahydrofuran (30 mL) was added diethyl oxalate (2.2 g, 15 mmol) and ethyl 4-phenoxybutanoate (2.08 g, 10 mmol) in tetrahydrofuran (30 mL) at 0° C. dropwise. The mixture was allowed to stir overnight, concentrated, quenched with 1 N HCl(aq), extracted with ethyl acetate, and concentrated. A fraction of this material (308 mg, 1 mmol) was added to concentrated H2SO4 at 0° C. The mixture was stirred for 1.5 hours and was poured onto ice chips. The precipitate was collected to afford the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 8.44 (dd, J=1.5, 8.1 Hz, 1H), 7.48 (t, J=8.1 Hz, 1H), 7.25 (t, J=7.8 Hz, 1H), 7.14 (d, J=8.4 Hz, 1H), 4.28 (t, J=5.1 Hz, 2H), and 3.02 (t, J=5.1 Hz, 2H). concentrated quenched with 1 N HCl(aq) extracted with ethyl acetate concentrated The mixture was stirred for 1.5 hours was poured onto ice chips The precipitate was collected