1-(1,4-dioxan-2-yl)ethanone

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

実験手順: To a solution of 1-(1,4-dioxan-2-yl)ethanone (12 g, 92.2 mmol) in 1,2-dichloroethane (100 mL) was added (4-methoxyphenyl)methanamine (25 g, 184.4 mmol) at room temperature. The mixture was allowed to stir for 3 hours, and then sodium triacetoxyborohydride (39 g, 184.4 mmol) was added. The resulting mixture was allowed to stir for 48 hours at room temperature. The reaction mixture was quenched by adding water, extracted with dichloromethane (100 mL×3). The combined organic phase was dried by anhydrous sodium sulphate, and then filtered. The filtrate was concentrated and purified by column chromatograph on silica gel (elute: dichloromethane/methanol 100:1→50:1→20:1) to give 1-(1,4-dioxan-2-yl)-N-(4-methoxybenzyl)ethanamine (16.4 g, 71%) as a yellow solid. LCMS (M+H+) m z: calcd. 251.15. found 251.9. To a solution of 1-(1,4-dioxan-2-yl)-N-(4-methoxybenzyl)ethanamine (5 g, 19.9 mmol) in anhydrous methanol (100 mL) was added palladium 10% on carbon (240 mg, 2 mmol), then purged with hydrogen (30 psi), the mixture was allowed to stir overnight at room temperature. The reaction mixture was filtered, and the filtrate was concentrated to afford the title compound (2.5 g, 96%) as a brown solid. to stir for 48 hours at room temperature The reaction mixture was quenched by adding water extracted with dichloromethane (100 mL×3) The combined organic phase was dried by anhydrous sodium sulphate filtered The filtrate was concentrated purified by column chromatograph on silica gel (elute: dichloromethane/methanol 100:1→50:1→20:1)

反応条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of benzoic peroxide (20 g, 141 mmol) in 200 mL 1,4-dioxane at room temperature under nitrogen atmosphere was added biacetyl (24.3 g, 282 mmol). After the addition, the mixture was heated to reflux and stirred for 24 hours. The reaction mixture was cooled to 0° C. The pH was adjusted to around 9 by progressively adding 2N sodium hydroxide below 0° C., extracted with 2-methoxy-2-methylpropane (10 mL×3), and concentrated to give 1-(1,4-dioxan-2-yl)ethanone (13 g, 36%) as a yellow oil which was used directly in the next step without purification. After the addition the mixture was heated to reflux extracted with 2-methoxy-2-methylpropane (10 mL×3) concentrated

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

実験手順: To a solution of 1-(1,4-dioxan-2-yl)ethanone (12 g, 92.2 mmol) in 1,2-dichloroethane (100 mL) was added (4-methoxyphenyl)methanamine (25 g, 184.4 mmol) at room temperature. The mixture was allowed to stir for 3 hours, and then sodium triacetoxyborohydride (39 g, 184.4 mmol) was added. The resulting mixture was allowed to stir for 48 hours at room temperature. The reaction mixture was quenched by adding water, extracted with dichloromethane (100 mL×3). The combined organic phase was dried by anhydrous sodium sulphate, and then filtered. The filtrate was concentrated and purified by column chromatograph on silica gel (elute: dichloromethane/methanol 100:1→50:1→20:1) to give 1-(1,4-dioxan-2-yl)-N-(4-methoxybenzyl)ethanamine (16.4 g, 71%) as a yellow solid. LCMS (M+H+) m/z: calcd. 251.15. found 251.9. To a solution of 1-(1,4-dioxan-2-yl)-N-(4-methoxybenzyl)ethanamine (5 g, 19.9 mmol) in anhydrous methanol (100 mL) was added palladium 10% on carbon (240 mg, 2 mmol), then purged with hydrogen (30 psi), the mixture was allowed to stir overnight at room temperature. The reaction mixture was filtered, and the filtrate was concentrated to afford the title compound (2.5 g, 96%) as a brown solid. to stir for 48 hours at room temperature The reaction mixture was quenched by adding water extracted with dichloromethane (100 mL×3) The combined organic phase was dried by anhydrous sodium sulphate filtered The filtrate was concentrated purified by column chromatograph on silica gel (elute: dichloromethane/methanol 100:1→50:1→20:1)

反応条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of benzoic peroxide (20 g, 141 mmol) in 200 mL 1,4-dioxane at room temperature under nitrogen atmosphere was added biacetyl (24.3 g, 282 mmol). After the addition, the mixture was heated to reflux and stirred for 24 hours. The reaction mixture was cooled to 0° C. The pH was adjusted to around 9 by progressively adding 2N sodium hydroxide below 0° C., extracted with 2-methoxy-2-methylpropane (10 mL×3), and concentrated to give 1-(1,4-dioxan-2-yl)ethanone (13 g, 36%) as a yellow oil which was used directly in the next step without purification. After the addition the mixture was heated to reflux extracted with 2-methoxy-2-methylpropane (10 mL×3) concentrated