3-bromo-3-methylbutan-2-one

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A stirred solution of 3-bromo-3-methylbutan-2-one (1 g, 6.1 mmol) in 50 mL of acetone and 5 mL of water was treated with NaN3 (0.4 g, 6.1 mmol). The reaction mixture was stirred at reflux for 18 hours and then evaporated to dryness. The residue was partitioned between ethyl acetate and water and the organic layer was washed with brine, evaporated to dryness to give 3-azido-3-methylbutan-2-one (0.5 g, 65%) which was used in the next step without further purification. LCMS: No molecular ion observed for desired mass. at reflux for 18 hours evaporated to dryness The residue was partitioned between ethyl acetate and water the organic layer was washed with brine evaporated to dryness

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A stirred solution of 3-bromo-3-methylbutan-2-one (1 g, 6.1 mmol) in 50 mL of acetone and 5 mL of water was treated with NaN3 (0.4 g, 6.1 mmol). The reaction mixture was stirred at reflux for 18 hours and then evaporated to dryness. The residue was partitioned between ethyl acetate and water and the organic layer was washed with brine, evaporated to dryness to give 3-azido-3-methylbutan-2-one (0.5 g, 65%) which was used in the next step without further purification. LCMS: No molecular ion observed for desired mass. at reflux for 18 hours evaporated to dryness The residue was partitioned between ethyl acetate and water the organic layer was washed with brine evaporated to dryness

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 1 mol of methyl bromoisopropyl ketone is added dropwise at 100° C. to a melt of 4 mols of pyrazole. The reaction mixture is stirred for a further hour. Following customary working up, 2-methyl-2-(pyrazol-1-yl)-butan-3one is obtained in a yield of 70%.

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 16.5 g (0.1 mol) of 3-bromo-3-methyl-2-butanone and 11.6 g (0.12 mol) of potassium rhodanide in 150 ml of anhydrous acetone are heated at reflux for about 11/2 hours. After cooling, the separated potassium bromide is filtered off under suction and backwashed with a small amount of acetone, and the filtrate is evaporated to dryness at 50° C. under reduced pressure. The residue is dissolved in 200 ml of diethyl ether and the solution is washed three times with 100 ml of water each time, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure.The crude product is fractionated on a short Vigreux column to yield 3-methyl-3-thiocyanato-2-butanone, b.p. 52° C./0.04 mmHg. at reflux for about 11/2 hours After cooling the separated potassium bromide is filtered off under suction the filtrate is evaporated to dryness at 50° C. under reduced pressure The residue is dissolved in 200 ml of diethyl ether the solution is washed three times with 100 ml of water each time dried over anhydrous sodium sulfate evaporated to dryness under reduced pressure

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 16.5 g (0.1 mol) of 3-bromo-3-methyl-2-butanone and 11.6 g (0.12 mol) of potassium rhodanide in 150 ml of anhydrous acetone are heated at reflux for about 11/2 hours. After cooling, the separated potassium bromide is filtered off under suction and backwashed with a small amount of acetone, and the filtrate is evaporated to dryness at 50° C. under reduced pressure. The residue is dissolved in 200 ml of diethyl ether and the solution is washed three times with 100 ml of water each time, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure.The crude product is fractionated on a short Vigreux column to yield 3-methyl-3-thiocyanato-2-butanone, b.p. 52° C./0.04 mmHg. at reflux for about 11/2 hours After cooling the separated potassium bromide is filtered off under suction the filtrate is evaporated to dryness at 50° C. under reduced pressure The residue is dissolved in 200 ml of diethyl ether the solution is washed three times with 100 ml of water each time dried over anhydrous sodium sulfate evaporated to dryness under reduced pressure

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A stirred solution of 3-bromo-3-methylbutan-2-one (1 g, 6.1 mmol) in 50 mL of acetone and 5 mL of water was treated with NaN3 (0.4 g, 6.1 mmol). The reaction mixture was stirred at reflux for 18 hours and then evaporated to dryness. The residue was partitioned between ethyl acetate and water and the organic layer was washed with brine, evaporated to dryness to give 3-azido-3-methylbutan-2-one (0.5 g, 65%) which was used in the next step without further purification. LCMS: No molecular ion observed for desired mass. at reflux for 18 hours evaporated to dryness The residue was partitioned between ethyl acetate and water the organic layer was washed with brine evaporated to dryness

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 16.5 g. (0.1 mol) of 3-bromo-3-methyl-2-butanone and 11.6 g. (0.12 mol) of potassium rhodanide were refluxed for 1-2 hours in 150 ml. of anhydrous acetone. After cooling, the separated potassium bromide was filtered under suction, back-washed with a small amount of acetone and evaporated to dryness in vacuo at 50° C. The residue was taken up in 200 ml. of ether and washed three times with 100 ml. of water. The ether phase was dried over sodium sulfate and evaporated to dryness in vacuo. The crude product was fractionated on a short Vigreux column to yield 3-methyl-3-thiocyanato-2-butanone, b.p. (0.04 mm), 52° C. After cooling the separated potassium bromide was filtered under suction back-washed with a small amount of acetone evaporated to dryness in vacuo at 50° C of ether and washed three times with 100 ml The ether phase was dried over sodium sulfate evaporated to dryness in vacuo

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 16.5 g. (0.1 mol) of 3-bromo-3-methyl-2-butanone and 11.6 g. (0.12 mol) of potassium rhodanide were refluxed for 1-2 hours in 150 ml. of anhydrous acetone. After cooling, the separated potassium bromide was filtered under suction, back-washed with a small amount of acetone and evaporated to dryness in vacuo at 50° C. The residue was taken up in 200 ml. of ether and washed three times with 100 ml. of water. The ether phase was dried over sodium sulfate and evaporated to dryness in vacuo. The crude product was fractionated on a short Vigreux column to yield 3-methyl-3-thiocyanato-2-butanone, b.p. (0.04 mm), 52° C. After cooling the separated potassium bromide was filtered under suction back-washed with a small amount of acetone evaporated to dryness in vacuo at 50° C of ether and washed three times with 100 ml The ether phase was dried over sodium sulfate evaporated to dryness in vacuo

反応条件: temp:0.00; pressure:0.00; stir: