3-methoxy-2,2-dimethylpropan-1-ol

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

Procedure: Methanesulfonyl chloride (330 mL) is added dropwise to a solution of 3-methoxy-2,2-dimethylpropan-1-ol (250 mg) and N,N-diisopropylethylamine (1.1 mL) in dichloromethane (3 mL) chilled in an ice bath. The mixture is stirred at room temperature for 12 hours and partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with twice with 1 N hydrochloric acid, saturated aqueous NaHCO3 solution and brine. Then the organic phase is dried (MgSO4) and concentrated to give the title compound. Yield: 407 mg; TLC: rf=0.75 (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 twice with 1 N hydrochloric acid, saturated aqueous NaHCO3 solution and brine Then the organic phase is dried (MgSO4) concentrated

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

Procedure: According to the procedure as described in Example 1,2,2-dimethyl-1-methoxy-3-[(dimethylphenylsilyl)oxy]propane was prepared from intermediate 2,2-dimethyl-3-methoxy-1-propanol and reagent dimethylphenylsilyl chloride.

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

Procedure: According to the procedure as described in Example 1,2,2-dimethyl-1-methoxy-3-[(dimethylphenylsilyl)oxy]propane was prepared from intermediate 2,2-dimethyl-3-methoxy-1-propanol and reagent dimethylphenylsilyl chloride.

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

Procedure: 1 g of 2,2-dimethyl-3-methoxy-1-propanol was admixed with 10 ml of N,N-dimethyl formamide, and 0.29 g of imidazole was added thereto. The mixture was cooled in ice-water bath, and 1.65 ml of triethyl amine was added thereto. After stirring for 5 minutes, 1.65 g of tert-butyldimethylsilyl chloride in 10 ml of N,N-dimethyl formamide was slowly added to the reaction mixture, and the mixture was stirred in ice-water bath for further 4 hours. The reaction mixture was diluted with 10 ml of water, and extracted twice with 20 ml of dichloromethane for each time. The combined dichloromethane extract was dried over anhydrous sodium sulfate. After filtration, the filtrate was evaporated to dryness to give 1.78 g of concentrate of 2,2-dimethyl-1-methoxy-3-[(tert-butyldimethylsilyl)oxy]-propane. The crude product was purified by column chromatography using petroleum ether as eluent, to give colorless pure compound. was added extracted twice with 20 ml of dichloromethane for each time The combined dichloromethane extract was dried over anhydrous sodium sulfate After filtration the filtrate was evaporated to dryness to give 1.78 g of concentrate of 2,2-dimethyl-1-methoxy-3-[(tert-butyldimethylsilyl)oxy]-propane The crude product was purified by column chromatography to give colorless pure compound

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

Procedure: According to the procedure as described in Example 1,2,2-dimethyl-1-methoxy-3-[(ethyldimethylsilyl)oxy]propane was prepared from intermediate 2,2-dimethyl-3-methoxy-1-propanol and reagent ethyldimethylsilyl chloride.

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

Procedure: According to the procedure as described in Example 1,2,2-dimethyl-1-methoxy-3-[(ethyldimethylsilyl)oxy]propane was prepared from intermediate 2,2-dimethyl-3-methoxy-1-propanol and reagent ethyldimethylsilyl chloride.

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

Procedure: 1 g of 2,2-dimethyl-3-methoxy-1-propanol was dissolved in 20 ml of dichloromethane. The resultant solution was cooled in ice-water bath to below 5° C., and 1.65 ml of triethyl amine was added thereto. After stirring the mixture for 5 minutes, 1.29 ml of trimethylsilyl chloride was added drop-wise to the reaction mixture, and the mixture was stirred in ice-water bath for further 2 hours, and at room temperature for further 1 hour. The reaction mixture was washed with water, and the organic layer separated was dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated to give 1.33 g of concentrate. The crude product was purified by column chromatography using petroleum ether as eluent, to give colorless pure compound. at room temperature for further 1 hour The reaction mixture was washed with water the organic layer separated was dried over anhydrous sodium sulfate After filtration the filtrate was concentrated to give 1.33 g of concentrate The crude product was purified by column chromatography to give colorless pure compound

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

Procedure: To a solution of 2',3'-di-O-acetyl-5'-deoxy-5-[2-(trimethylsilyl)-ethynyl]cytidine (100 mg, 0.25 mmol) and triphosgene (73 mg, 0.25 mmol) in dry dichloromethane (3 ml) there was added a solution of 3-methoxy-2,2-dimethylpropanol (77 mg, 0.65 mmol) [ref. Tetrahedron Asymmetry,1995,6, 271-282] and diisopropylethylamine (182 ml,1.3 mmol) in dry dichloromethane (2 ml). After stirring for 30 min at room temperature under Ar, methanol (0.5 ml) and water (0.5 ml) were added dropwise to the reaction mixture at room temperature. After stirring for an additional 5 minutes, the reaction mixture was partitioned between dichloromethane and water. The aqueous layer was extracted with dichloromethane. The combined organic layers were washed with brine, dried over anhydrous MgSO4 and filtered. The filtrate was evaporated under reduced pressure. Purification of the residue by preparative thin layer chromatography on silica gel (using n-hexane:ethyl acetate=1:1 as a developing solvent) gave 2',3'-di-O-acetyl-5'-deoxy- N4 -[(3-methoxy-2,2-dimethylpropoxy)carbonyl]-5-[2-(trimethylsilyl)ethynyl]-cytidine (107 mg,79%). were added dropwise to the reaction mixture at room temperature the reaction mixture was partitioned between dichloromethane and water The aqueous layer was extracted with dichloromethane The combined organic layers were washed with brine dried over anhydrous MgSO4 filtered The filtrate was evaporated under reduced pressure Purification of the residue by preparative thin layer chromatography on silica gel (

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

Procedure: To a solution of 2',3'-di-O-acetyl-5'-deoxy-5-[2-(trimethylsilyl)-ethynyl]cytidine (100 mg, 0.25 mmol) and triphosgene (73 mg, 0.25 mmol) in dry dichloromethane (3 ml) there was added a solution of 3-methoxy-2,2-dimethylpropanol (77 mg, 0.65 mmol) [ref. Tetrahedron Asymmetry,1995,6, 271-282] and diisopropylethylamine (182 ml,1.3 mmol) in dry dichloromethane (2 ml). After stirring for 30 min at room temperature under Ar, methanol (0.5 ml) and water (0.5 ml) were added dropwise to the reaction mixture at room temperature. After stirring for an additional 5 minutes, the reaction mixture was partitioned between dichloromethane and water. The aqueous layer was extracted with dichloromethane. The combined organic layers were washed with brine, dried over anhydrous MgSO4 and filtered. The filtrate was evaporated under reduced pressure. Purification of the residue by preparative thin layer chromatography on silica gel (using n-hexane:ethyl acetate=1:1 as a developing solvent) gave 2',3'-di-O-acetyl-5'-deoxy- N4 -[(3-methoxy-2,2-dimethylpropoxy)carbonyl]-5-[2-(trimethylsilyl)ethynyl]-cytidine (107 mg,79%). were added dropwise to the reaction mixture at room temperature the reaction mixture was partitioned between dichloromethane and water The aqueous layer was extracted with dichloromethane The combined organic layers were washed with brine dried over anhydrous MgSO4 filtered The filtrate was evaporated under reduced pressure Purification of the residue by preparative thin layer chromatography on silica gel (

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

Procedure: Methanesulfonyl chloride (330 mL) is added dropwise to a solution of 3-methoxy-2,2-dimethylpropan-1-ol (250 mg) and N,N-diisopropylethylamine (1.1 mL) in dichloromethane (3 mL) chilled in an ice bath. The mixture is stirred at room temperature for 12 hours and partitioned between saturated aqueous NaHCO3 solution and dichloromethane. The organic phase is washed with twice with 1 N hydrochloric acid, saturated aqueous NaHCO3 solution and brine. Then the organic phase is dried (MgSO4) and concentrated to give the title compound. Yield: 407 mg; TLC: rf=0.75 (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 twice with 1 N hydrochloric acid, saturated aqueous NaHCO3 solution and brine Then the organic phase is dried (MgSO4) concentrated

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

Procedure: 1 g of 2,2-dimethyl-3-methoxy-1-propanol was dissolved in 20 ml of dichloromethane. The resultant solution was cooled in ice-water bath to below 5° C., and 1.65 ml of triethyl amine was added thereto. After stirring the mixture 5 minutes, 1.29 ml of trimethylsilyl chloride was added drop-wise to the reaction mixture, and the mixture was stirred in ice-water bath for further 2 hours, and at room temperature for further 1 hour. The reaction mixture was washed with water, and the organic layer separated was dried over anhydrous sodium sulfate. After filtration, the filtrate was evaporated to give 1.33 g of concentrate. The crude product was purified by column chromatography using petroleum ether as eluent, to give colorless pure compound. was added drop-wise to the reaction mixture The reaction mixture was washed with water the organic layer separated was dried over anhydrous sodium sulfate After filtration the filtrate was evaporated to give 1.33 g of concentrate The crude product was purified by column chromatography to give colorless pure compound

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

Procedure: According to the procedure as described in Example 1,2,2-dimethyl-1-methoxy-3-[(dimethylphenylsilyl)oxy]propane was prepared from intermediate 2,2-dimethyl-3-methoxy-1-propanol and reagent dimethylphenylsilyl chloride.