2-bromo-1-(2,3-dihydro-1,4-benzodioxin-3-yl)ethanone

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

Procedure: The starting material is prepared as follows: To the solution of 42 g of 2-(2-bromoacetyl)-1,4-benzodioxan in 360 ml of methanol, 12 g of sodium borohydride are added while stirring and keeping the temperature below 10°. After 5 hours, the mixture is cooled to 0° and 13.2 g of sodium hydroxide in 150 ml of methanol are added and the mixture kept at -15° overnight. It is poured onto ice, extracted with diethyl ether, the extract washed with saturated aqueous sodium chloride, dried and evaporated, to yield the 1,4-benzodioxan-2-yl-ethyleneoxide. The starting material is prepared the temperature below 10° the mixture is cooled to 0° the mixture kept at -15° overnight It is poured onto ice extracted with diethyl ether the extract washed with saturated aqueous sodium chloride dried evaporated

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

Procedure: 1-[2-Thienyl]-3-[1-(2-[1,4-benzodioxan-2-yl]-2-oxoethyl)piperid-4-yl]urea, prepared by reacting 1-(piperid-4-yl)-3-(2-thienyl)urea with 2-bromoacetyl-1,4-benzodioxan in DMF/Et3N, may be reduced using sodium borohydride in 2 N sodium hydroxide to give the title compound.

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

Procedure: 1-Cyclohexylcarbonyl-3-[1-(2-[1,4-benzodioxan-2-yl]-2-oxoethyl)piperid-4-yl]urea, prepared by reacting 1-cyclohexylcarbonyl-3-(piperid-4-yl)urea with 2 -bromoacetyl-1,4-benzodioxan in DMF/Et3N, may be reduced using sodium borohydride in 2 N sodium hydroxide to give the title compound.

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromoacetyl-1,4-benzodioxan(53.8 g) in methanol (500 mls) was cooled to -70° C. Sodium borohydride (10.3 g) was added and the solution stirred at -70° C. for 12 hours. The solution was treated with hydrobromic acid until acidic and the solvent evaporated. The residue was dissolved in ether and the ether extracts were washed with sodium bicarbonate solution; then water and dried (MgSO4) and evaporated to give a white solid. This was recrystallised eight times from petroleum spirit 60-80 to give 14 grams of the title compound. evaporated The residue was dissolved in ether the ether extracts were washed with sodium bicarbonate solution then water and dried (MgSO4) evaporated to give a white solid This was recrystallised eight times from petroleum spirit 60-80

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

Procedure: 1-Benzoyl-3-(piperid-4-yl)urea (2.46 g, 0.01 mol) and 2-bromoacetyl-1,4-benzodioxan (2.57 g, 0.01 mol) in dry dimethylformamide (40 mls) were stirred at room temperature. Triethylamine (1,1 g, 1.5 cm3) was added and the suspension stirred for 1 hour. Water was added and the solid filtered off (4.20 g, 100%). The solid was suspended in methanol (40 mls) and ethanolic hydrogen chloride added until the solution was acidic. The title compound was filtered off as the hydrochloride salt and dried (yield 3.51 gm 76% yield). Melting pt. 160°-161° C. the solid filtered off (4.20 g, 100%) ethanolic hydrogen chloride added until the solution The title compound was filtered off as the hydrochloride salt dried (yield 3.51 gm 76% yield)

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

Procedure: The starting material is prepared as follows: To the solution of 42 g of 2-(2-bromoacetyl)-1,4-benzodioxan in 360 ml of methanol, 12 g of sodium borohydride are added while stirring and keeping the temperature below 10°. After five hours, the mixture is cooled to 0° and 13.2 g of sodium hydroxide in 150 ml of methanol are added and the mixture kept at -15° overnight. It is poured onto ice, extracted with diethyl ether, the extract washed with saturated aqueous sodium chloride, dried and evaporated, to yield the 1,4-benzodioxan-2-yl-ethyleneoxide. The starting material is prepared the temperature below 10° the mixture is cooled to 0° the mixture kept at -15° overnight It is poured onto ice extracted with diethyl ether the extract washed with saturated aqueous sodium chloride dried evaporated

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

Procedure: 1-[2-Thienyl]-3-[1-(2-[1,4-benzodioxan-2-yl]-2-oxoethyl)piperid-4-yl]urea, prepared by reacting 1-(piperid-4-yl)-3-(2-thienyl)urea with 2-bromoacetyl-1,4-benzodioxan in DMF/Et3N, may be reduced using sodium borohydride in 2 N sodium hydroxide to give the title compound.

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

Procedure: 1-Cyclohexylcarbonyl-3-[1-(2-[1,4-benzodioxan-2-yl]-2-oxoethyl)piperid-4-yl]urea, prepared by reacting 1-cyclohexylcarbonyl-3-(piperid-4-yl)urea with 2 -bromoacetyl-1,4-benzodioxan in DMF/Et3N, may be reduced using sodium borohydride in 2 N sodium hydroxide to give the title compound.

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromoacetyl-1,4-benzodioxan(53.8 g) in methanol (500 mls) was cooled to -70° C. Sodium borohydride (10.3 g) was added and the solution stirred at -70° C. for 12 hours. The solution was treated with hydrobromic acid until acidic and the solvent evaporated. The residue was dissolved in ether and the ether extracts were washed with sodium bicarbonate solution; then water and dried (MgSO4) and evaporated to give a white solid. This was recrystallised eight times from petroleum spirit 60-80 to give 14 grams of the title compound. evaporated The residue was dissolved in ether the ether extracts were washed with sodium bicarbonate solution then water and dried (MgSO4) evaporated to give a white solid This was recrystallised eight times from petroleum spirit 60-80

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

Procedure: 1-Benzoyl-3-(piperid-4-yl)urea (2.46 g, 0.01 mol) and 2-bromoacetyl-1,4-benzodioxan (2.57 g, 0.01 mol) in dry dimethylformamide (40 mls) were stirred at room temperature. Triethylamine (1,1 g, 1.5 cm3) was added and the suspension stirred for 1 hour. Water was added and the solid filtered off (4.20 g, 100%). The solid was suspended in methanol (40 mls) and ethanolic hydrogen chloride added until the solution was acidic. The title compound was filtered off as the hydrochloride salt and dried (yield 3.51 gm 76% yield). Melting pt. 160°-161° C. the solid filtered off (4.20 g, 100%) ethanolic hydrogen chloride added until the solution The title compound was filtered off as the hydrochloride salt dried (yield 3.51 gm 76% yield)

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

Procedure: The starting material is prepared as follows: To the solution of 42 g of 2-(2-bromoacetyl)-1,4-benzodioxan in 360 ml of methanol, 12 g of sodium borohydride are added while stirring and keeping the temperature below 10°. After five hours, the mixture is cooled to 0° and 13.2 g of sodium hydroxide in 150 ml of methanol are added and the mixture kept at -15° overnight. It is poured onto ice, extracted with diethyl ether, the extract washed with saturated aqueous sodium chloride, dried and evaporated, to yield the 1,4-benzodioxan-2-yl-ethyleneoxide. The starting material is prepared the temperature below 10° the mixture is cooled to 0° the mixture kept at -15° overnight It is poured onto ice extracted with diethyl ether the extract washed with saturated aqueous sodium chloride dried evaporated

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

Procedure: The starting material is prepared as follows: To the solution of 42 g of 2-(2-bromoacetyl)-1,4-benzodioxan in 360 ml of methanol, 12 g of sodium borohydride are added while stirring and keeping the temperature below 10°. After five hours, the mixture is cooled to 0° and 13.2 g of sodium hydroxide in 150 ml of methanol are added and the mixture kept at -15° overnight. It is poured onto ice, extracted with diethyl ether, the extract washed with saturated aqueous sodium chloride, dried and evaporated, to yield the 1,4-benzodioxan-2-yl-ethyleneoxide. The starting material is prepared the temperature below 10° the mixture is cooled to 0° the mixture kept at -15° overnight It is poured onto ice extracted with diethyl ether the extract washed with saturated aqueous sodium chloride dried evaporated