5,5-Dimethyl-1,3,2-dioxathiane 2-oxide

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

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

Procedure: To a mixture of 4-bromo-3,5-dimethylphenol (625 mg) and Cs2CO3 (5 g) in N,N-dimethylformamide (10 mL) is added 5,5-dimethyl-[1,3,2]dioxathiane-2-oxide (467 mg). The mixture is stirred for 12 hours at 100° C. and then partitioned between water and ethyl acetate. The organic phase is washed with brine and dried (MgSO4). The solvent is evaporated and the residue is purified by HPLC on reversed phase to give the title compound. Yield: 251 mg; LC (method 7): tR=1.16 min; Mass spectrum (ESI+): m/z=287 [M+H]+. partitioned between water and ethyl acetate The organic phase is washed with brine dried (MgSO4) The solvent is evaporated the residue is purified by HPLC on reversed phase

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2,2-dimethyl-propane-1,3-diol (1 g) in dichloromethane (5 mL) is added dropwise at 0° C. thionylchloride (735 μL). The mixture is stirred for 3 hours at 40° C. and then partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with brine and dried (MgSO4). The solvent is evaporated to give the title compound. Yield: 1 g; TLC: rf=0.65 (silicagel, cyclohexane/ethyl acetate 3:1). partitioned between saturated aqueous NaHCO3 solution and dichloromethane The organic phase is washed with brine dried (MgSO4) The solvent is evaporated

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a microwave vial Cs2CO3 (5.4 g) is added to a solution of 5,5-dimethyl-[1,3,2]dioxathiane 2-oxide (500 mg) and 4-bromo-3,5-dimethylphenol (670 mg) in N,N-dimethylformamide (5 mL). The vial is sealed and the mixture is heated to 120° C. for 12 hours. The mixture is partitioned between ethyl acetate and water. The organic phase is washed three times with 2 M aqueous NaOH and with brine. After drying (MgSO4) and concentration the residue is chromatographed on silica gel (cyclohexane/ethyl acetate 99:1→50:50) to give the title compound. Yield: 372 mg; LC (method 7): tR=1.17 min; Mass spectrum (ESI+): m/z=287 [M+H]+. The vial is sealed The mixture is partitioned between ethyl acetate and water The organic phase is washed three times with 2 M aqueous NaOH After drying (MgSO4) and concentration the residue is chromatographed on silica gel (cyclohexane/ethyl acetate 99:1→50:50)

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Thionylchloride (735 mL) is added to a solution of 2,2-dimethylpropane-1,3-diol (1 g) in dichloromethane (10 mL) chilled in an ice bath. The mixture is heated to 40° C. for 3 hours and partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with brine, dried (MgSO4) and concentrated to give the title compound. Yield: 535 mg; TLC: rf=0.65 (silicagel, cyclohexane/ethyl acetate 3:1). chilled in an ice bath partitioned between saturated aqueous NaHCO3 solution and dichloromethane The organic phase is washed with brine dried (MgSO4) concentrated

Conditions: temp:30.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.0 g (0.064 mol) of 5,5-dimethyl-1,3,2-dioxathiane-2-oxide was introduced at 20° C. in 100 ml of methylene chloride and 50 ml of water in a 250 ml three-necked flask. 0.02 g of 90 percent ruthenium trichloride was added as a catalyst. 152.45 g (0.0727 mol) of sodium hypochlorite in water was added with stirring for 20 minutes, and the temperature increased to 30° C. The reaction mixture was stirred for five more hours and mixed with 10 drops of isopropanol; the yellow color faded and a black precipitate formed. The water phase was extracted twice with methylene chloride (50 ml), and the combined organic phases were extracted with NaHCO3 solution (100 ml), dried with Na2SO4 and concentrated by evaporation. The white crystalline product was dried overnight at room temperature at a pressure of 15 mbars and weighed 10.65 g, which corresponded to a yield of 99 percent, relative to the 5,5-dimethyl-1,3,2-dioxathiane-2-oxide used. The reaction mixture was stirred for five more hours a black precipitate formed The water phase was extracted twice with methylene chloride (50 ml) the combined organic phases were extracted with NaHCO3 solution (100 ml) dried with Na2SO4 concentrated by evaporation The white crystalline product was dried overnight at room temperature at a pressure of 15 mbars

Conditions: temp:30.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.0 g (0.064 mol) of 5,5-dimethyl-1,3,2-dioxathiane-2-oxide was introduced at 20° C. in 100 ml of methylene chloride and 50 ml of water in a 250 ml three-necked flask. 0.02 g of 90 percent ruthenium trichloride was added as a catalyst. 152.45 g (0.0727 mol) of sodium hypochlorite in water was added with stirring for 20 minutes, and the temperature increased to 30° C. The reaction mixture was stirred for five more hours and mixed with 10 drops of isopropanol; the yellow color faded and a black precipitate formed. The water phase was extracted twice with methylene chloride (50 ml), and the combined organic phases were extracted with NaHCO3 solution (100 ml), dried with Na2SO4 and concentrated by evaporation. The white crystalline product was dried overnight at room temperature at a pressure of 15 mbars and weighed 10.65 g, which corresponded to a yield of 99 percent, relative to the 5,5-dimethyl-1,3,2-dioxathiane-2-oxide used. The reaction mixture was stirred for five more hours a black precipitate formed The water phase was extracted twice with methylene chloride (50 ml) the combined organic phases were extracted with NaHCO3 solution (100 ml) dried with Na2SO4 concentrated by evaporation The white crystalline product was dried overnight at room temperature at a pressure of 15 mbars

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

Procedure: 25.36 g (0.24 mol) of 2,2-dimethylpropane-1,3-diol was suspended at room temperature in 150 ml of methylene chloride in a 500 ml three-necked flask. 37.36 g (0.31 mol) of thionyl chloride was instilled over 30 minutes. After the end of the addition, the reaction solution was held at reflux for 1.5 hours and then cooled to room temperature. 100 ml of water was added to the reaction. The aqueous phase was discarded; the organic phase was extracted three times with saturated NaHCO3 solution (100 ml), then dried with Na2SO4 and concentrated by evaporation on a rotary evaporator. The residue was distilled at 24 mbars and 78° C. The product was a pure colorless liquid according to GC and weighed 23.4 g, which corresponded to a yield of 92 percent. After the end of the addition at reflux for 1.5 hours the organic phase was extracted three times with saturated NaHCO3 solution (100 ml) dried with Na2SO4 concentrated by evaporation on a rotary evaporator The residue was distilled at 24 mbars and 78° C

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

Procedure: To a mixture of 4-bromo-3,5-dimethylphenol (625 mg) and Cs2CO3 (5 g) in N,N-dimethylformamide (10 mL) is added 5,5-dimethyl-[1,3,2]dioxathiane-2-oxide (467 mg). The mixture is stirred for 12 hours at 100° C. and then partitioned between water and ethyl acetate. The organic phase is washed with brine and dried (MgSO4). The solvent is evaporated and the residue is purified by HPLC on reversed phase to give the title compound. Yield: 251 mg; LC (method 7): tR=1.16 min; Mass spectrum (ESI+): m/z=287 [M+H]+. partitioned between water and ethyl acetate The organic phase is washed with brine dried (MgSO4) The solvent is evaporated the residue is purified by HPLC on reversed phase

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2,2-dimethyl-propane-1,3-diol (1 g) in dichloromethane (5 mL) is added dropwise at 0° C. thionylchloride (735 μL). The mixture is stirred for 3 hours at 40° C. and then partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with brine and dried (MgSO4). The solvent is evaporated to give the title compound. Yield: 1 g; TLC: rf=0.65 (silicagel, cyclohexane/ethyl acetate 3:1). partitioned between saturated aqueous NaHCO3 solution and dichloromethane The organic phase is washed with brine dried (MgSO4) The solvent is evaporated

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a microwave vial Cs2CO3 (5.4 g) is added to a solution of 5,5-dimethyl-[1,3,2]dioxathiane 2-oxide (500 mg) and 4-bromo-3,5-dimethylphenol (670 mg) in N,N-dimethylformamide (5 mL). The vial is sealed and the mixture is heated to 120° C. for 12 hours. The mixture is partitioned between ethyl acetate and water. The organic phase is washed three times with 2 M aqueous NaOH and with brine. After drying (MgSO4) and concentration the residue is chromatographed on silica gel (cyclohexane/ethyl acetate 99:1→50:50) to give the title compound. Yield: 372 mg; LC (method 7): tR=1.17 min; Mass spectrum (ESI+): m/z=287 [M+H]+. The vial is sealed The mixture is partitioned between ethyl acetate and water The organic phase is washed three times with 2 M aqueous NaOH After drying (MgSO4) and concentration the residue is chromatographed on silica gel (cyclohexane/ethyl acetate 99:1→50:50)

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Thionylchloride (735 mL) is added to a solution of 2,2-dimethylpropane-1,3-diol (1 g) in dichloromethane (10 mL) chilled in an ice bath. The mixture is heated to 40° C. for 3 hours and partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with brine, dried (MgSO4) and concentrated to give the title compound. Yield: 535 mg; TLC: rf=0.65 (silicagel, cyclohexane/ethyl acetate 3:1). chilled in an ice bath partitioned between saturated aqueous NaHCO3 solution and dichloromethane The organic phase is washed with brine dried (MgSO4) concentrated