(1-methyl-2,6,7-trioxabicyclo[2.2.2]octan-4-yl)methanol

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

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a flask equipped with a stirrer, a distilling column, a nitrogen inlet, a heating jacket, and a thermometer were charged 486 g of triethyl orthoacetate, 408 g of pentaerythritol, 300 g of diethylene glycol dimethyl ether, and 0.9 g of PTSA. The mixture was gradually heated to 170° C. over a period of 5 hours. During this time 490 g of distillate were obtained. The distillate contained mostly ethanol and small amounts of diethylene glycol dimethyl ether. The temperature was lowered to 100° C., and the remaining diethylene glycol dimethyl ether was distilled off under reduced pressure (30 mbar). The residue was subjected to vacuum distillation. The fraction having a boiling temperature of 126-130° C. at a pressure of 4 mbar yielded 426 g of oil. This oil solidified to a clear solid having a melting point of 99° C. and had the following structure Into a flask equipped with a stirrer During this time 490 g of distillate were obtained was lowered to 100° C. the remaining diethylene glycol dimethyl ether was distilled off under reduced pressure (30 mbar) The residue was subjected to vacuum distillation

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a flask equipped with a stirrer, a distilling column, a nitrogen inlet, a heating jacket, and a thermometer were charged 486 g of triethyl orthoacetate, 408 g of pentaerythritol, 300 g of diethylene glycol dimethyl ether, and 0.9 g of PTSA. The mixture was gradually heated to 170° C. over a period of 5 hours. During this time 490 g of distillate were obtained. The distillate contained mostly ethanol and small amounts of diethylene glycol dimethyl ether. The temperature was lowered to 100° C., and the remaining diethylene glycol dimethyl ether was distilled off under reduced pressure (30 mbar). The residue was subjected to vacuum distillation. The fraction having a boiling temperature of 126-130° C. at a pressure of 4 mbar yielded 426 g of oil. This oil solidified to a clear solid having a melting point of 99° C. and had the following structure Into a flask equipped with a stirrer During this time 490 g of distillate were obtained was lowered to 100° C. the remaining diethylene glycol dimethyl ether was distilled off under reduced pressure (30 mbar) The residue was subjected to vacuum distillation

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

Procedure: To a solution of 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane (10.0 g, 0.062 mol) in 200 mL of acetone is added Jones reagent (chromium trioxide and sulfuric acid) until an orange color persisted. The excess oxidant is removed by the addition of 2-propanol until a green color is obtained and the solvents are evaporated under reduced pressure. The residue is partitioned between dichloromethane (100 mL) and water (50 mL) and the layers are separated. The organic layer is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to give 4-carboxy-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane. The excess oxidant is removed by the addition of 2-propanol until a green color is obtained the solvents are evaporated under reduced pressure The residue is partitioned between dichloromethane (100 mL) and water (50 mL) the layers are separated The organic layer is washed with water dried over anhydrous sodium sulfate evaporated under reduced pressure

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

Procedure: Powdered potassium hydroxide (16.2 g, 0.290 mol) is suspended in 100 mL of dimethyl sulfoxide and the mixture is stirred at 25° C. for 5 min. Then 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.21octane (10.0 g, 0.062 mol) is added followed by bromomethyl methyl ether (9.3 g, 6.1 mL, 0.074 mol). The reaction mixture is stirred for 30 min and then diluted with water (1 L) and extracted with dichloromethane several times. The combined organic layers are washed with saturated sodium chloride (100 mL), dried over anhydrous sodium sulfate and evaporated under reduced pressure to give 4-(methoxy)-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane. This crude material is dissolved in methanol (100 mL) and stirred with pyridinium p-toluenesulfonate (1.6 g, 6.200 mmol) in water (100 mL) for 30 min. The pH of the solution is adjusted to 7 with solid sodium bicarbonate and the solvents are removed under reduced pressure. The resulting solids are triturated with methanol and the methanol solution is evaporated to give 2-(methoxymethoxy)-1,1,1-tris(hydroxymethyl)ethane. The reaction mixture is stirred for 30 min extracted with dichloromethane several times The combined organic layers are washed with saturated sodium chloride (100 mL) dried over anhydrous sodium sulfate evaporated under reduced pressure

Conditions: temp:125.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of pentaerythritol (13.6 g, 0.100 mol) in 10 mL of toluene was added freshly distilled triethyl orthoacetate (16.2 g. 18.3 mL, 0.100 mol) and p-toluenesulfonic acid monohydrate (50 mg). The mixture was slowly heated in an oil bath and ethanol was distilled from the mixture over a period of 12 hrs. After removal of the ethanol, the bath temperature was raised to 125° C. and toluene was distilled off until the solution was homogeneous (about 30 mL). The residue was sublimed (bulb to bulb, ~130--C, 2.5 mmHg) to give 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.21octane (15.0 g, 0.093 mol, 93%). The mixture was slowly heated in an oil bath ethanol was distilled from the mixture over a period of 12 hrs After removal of the ethanol toluene was distilled off until the solution

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a dimethylsulfoxide solution (30 ml) of the (1-methyl-2,6,7-trioxabicyclo[2.2.2]oct-4-yl)methanol (4.5 g, 28.1 mmol) obtained in the step (24a), sodium hydride, in oil (1.29 g, 29.5 mmol as the content was regarded as 55%) was added at room temperature. To the mixture, 4-chloro-2,3-dimethylpyridine 1-oxide (3.99 g, 25.3 mmol) was added, which was stirred at 60° C. for 3 hours. After cooled to room temperature, the reaction mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/methanol) to obtain the title compound (7.46 g, yield: 81%) as a yellow oil. was added at room temperature After cooled to room temperature the reaction mixture was concentrated under reduced pressure The residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/methanol)

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of pentaerythritol (15 g, 110 mmol), triethyl orthoacetate (20.2 ml, 110 mmol), and p-toluenesulfonic acid monohydrate (947 mg, 5.5 mmol) was stirred at 100° C. for 30 minutes. The temperature of the mixture was further raised to 130° C. and the mixture was stirred for 30 minutes. To the reaction mixture, triethylamine (1.53 ml, 11 mmol) was added and the reaction mixture was concentrated. The residue was purified by silica gel column chromatography (elution solvent: heptane/ethyl acetate) to obtain the title compound (8.5 g, yield: 48.2%) as a light yellow solid. The temperature of the mixture was further raised to 130° C. the mixture was stirred for 30 minutes the reaction mixture was concentrated The residue was purified by silica gel column chromatography (elution solvent: heptane/ethyl acetate)

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

Procedure: To a solution of 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane (10.0 g, 0.062 mol) in 200 mL of acetone is added Jones reagent (chromium trioxide and sulfuric acid) until an orange color persisted. The excess oxidant is removed by the addition of 2-propanol until a green color is obtained and the solvents are evaporated under reduced pressure. The residue is partitioned between dichloromethane (100 mL) and water (50 mL) and the layers are separated. The organic layer is washed with water, dried over anhydrous sodium sulfate and evaporated under reduced pressure to give 4-carboxy-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane. The excess oxidant is removed by the addition of 2-propanol until a green color is obtained the solvents are evaporated under reduced pressure The residue is partitioned between dichloromethane (100 mL) and water (50 mL) the layers are separated The organic layer is washed with water dried over anhydrous sodium sulfate evaporated under reduced pressure

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

Procedure: Powdered potassium hydroxide (16.2 g, 0.290 mol) is suspended in 100 mL of dimethyl sulfoxide and the mixture is stirred at 25° C. for 5 min. Then 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.21octane (10.0 g, 0.062 mol) is added followed by bromomethyl methyl ether (9.3 g, 6.1 mL, 0.074 mol). The reaction mixture is stirred for 30 min and then diluted with water (1 L) and extracted with dichloromethane several times. The combined organic layers are washed with saturated sodium chloride (100 mL), dried over anhydrous sodium sulfate and evaporated under reduced pressure to give 4-(methoxy)-1-methyl-2,6,7-trioxabicyclo[2.2.2]octane. This crude material is dissolved in methanol (100 mL) and stirred with pyridinium p-toluenesulfonate (1.6 g, 6.200 mmol) in water (100 mL) for 30 min. The pH of the solution is adjusted to 7 with solid sodium bicarbonate and the solvents are removed under reduced pressure. The resulting solids are triturated with methanol and the methanol solution is evaporated to give 2-(methoxymethoxy)-1,1,1-tris(hydroxymethyl)ethane. The reaction mixture is stirred for 30 min extracted with dichloromethane several times The combined organic layers are washed with saturated sodium chloride (100 mL) dried over anhydrous sodium sulfate evaporated under reduced pressure

Conditions: temp:125.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of pentaerythritol (13.6 g, 0.100 mol) in 10 mL of toluene was added freshly distilled triethyl orthoacetate (16.2 g. 18.3 mL, 0.100 mol) and p-toluenesulfonic acid monohydrate (50 mg). The mixture was slowly heated in an oil bath and ethanol was distilled from the mixture over a period of 12 hrs. After removal of the ethanol, the bath temperature was raised to 125° C. and toluene was distilled off until the solution was homogeneous (about 30 mL). The residue was sublimed (bulb to bulb, ~130--C, 2.5 mmHg) to give 4-(hydroxymethyl)-1-methyl-2,6,7-trioxabicyclo[2.2.21octane (15.0 g, 0.093 mol, 93%). The mixture was slowly heated in an oil bath ethanol was distilled from the mixture over a period of 12 hrs After removal of the ethanol toluene was distilled off until the solution

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a dimethylsulfoxide solution (30 ml) of the (1-methyl-2,6,7-trioxabicyclo[2.2.2]oct-4-yl)methanol (4.5 g, 28.1 mmol) obtained in the step (24a), sodium hydride, in oil (1.29 g, 29.5 mmol as the content was regarded as 55%) was added at room temperature. To the mixture, 4-chloro-2,3-dimethylpyridine 1-oxide (3.99 g, 25.3 mmol) was added, which was stirred at 60° C. for 3 hours. After cooled to room temperature, the reaction mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/methanol) to obtain the title compound (7.46 g, yield: 81%) as a yellow oil. was added at room temperature After cooled to room temperature the reaction mixture was concentrated under reduced pressure The residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/methanol)