3-bromo-1-methylpyrrolidin-2-one

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

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

Procedure: To a solution of 4-bromo-3,5-dimethylphenol (100 mg) in N,N-dimethylformamide (2 mL) is added 3-bromo-1-methylpyrrolidin-2-one (100 mg) and K2CO3 (105 mg). The mixture is stirred for 12 hours at room temperature. Then the mixture is partitioned between water and diethylether. The organic phase is dried (MgSO4) and concentrated. The residue is chromatographed on silica gel (cyclohexane/ethyl acetate 80:20→50:50) to give the title compound. Yield: 65 mg; LC (method 7): tR=1.0 min; Mass spectrum (ESI+): m/z=298 [M+H]+. Then the mixture is partitioned between water and diethylether The organic phase is dried (MgSO4) concentrated The residue is chromatographed on silica gel (cyclohexane/ethyl acetate 80:20→50:50)

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

Procedure: There is also provided by this invention a method for preparation of 3-hydroxy-N-methylpyrrolidone which comprises conversion of delta-butyrolactone to methyl-2,4-dibromobutyrate, conversion of the methyl-2,4-dibromobutyrate to N-methyl-2,4-dibromobutyramide, ring closure of the N-methyl-2,4-dibromobutyramide to form 3-bromo-N-methyl-2-pyrrolidone, and conversion of the 3-bromo-N-methyl-2-pyrrolidone to 3-hydroxy-N-methyl-2-pyrrolidone by reaction with alkali metal carbonate. There is also provided by this invention a method

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

Procedure: There is also provided by this invention a method for preparation of 3-hydroxy-N-methylpyrrolidone which comprises conversion of delta-butyrolactone to methyl-2,4-dibromobutyrate, conversion of the methyl-2,4-dibromobutyrate to N-methyl-2,4-dibromobutyramide, ring closure of the N-methyl-2,4-dibromobutyramide to form 3-bromo-N-methyl-2-pyrrolidone, and conversion of the 3-bromo-N-methyl-2-pyrrolidone to 3-hydroxy-N-methyl-2-pyrrolidone by reaction with alkali metal carbonate. There is also provided by this invention a method

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

Procedure: There is also provided by this invention a method for preparation of 3-hydroxy-N-methylpyrrolidone which comprises conversion of delta-butyrolactone to methyl-2,4-dibromobutyrate, conversion of the methyl-2,4-dibromobutyrate to N-methyl-2,4-dibromobutyramide, ring closure of the N-methyl-2,4-dibromobutyramide to form 3-bromo-N-methyl-2-pyrrolidone, and conversion of the 3-bromo-N-methyl-2-pyrrolidone to 3-hydroxy-N-methyl-2-pyrrolidone by reaction with alkali metal carbonate. There is also provided by this invention a method

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

Procedure: There is also provided by this invention a method for preparation of 3-hydroxy-N-methylpyrrolidone which comprises conversion of delta-butyrolactone to methyl-2,4-dibromobutyrate, conversion of the methyl-2,4-dibromobutyrate to N-methyl-2,4-dibromobutyramide, ring closure of the N-methyl-2,4-dibromobutyramide to form 3-bromo-N-methyl-2-pyrrolidone, and conversion of the 3-bromo-N-methyl-2-pyrrolidone to 3-hydroxy-N-methyl-2-pyrrolidone by reaction with alkali metal carbonate. There is also provided by this invention a method

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

Procedure: 2.7 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2hydroxyiminoacetate are dissolved in 12 ml of dimethylsulfoxide, and 1.0 g of anhydrous potassium carbonate is added thereto under nitrogen gas atmosphere. The mixture is stirred at room temperature for 10 minutes. 1.2 g of 1-methyl-3-bromo-2-pyrrolidone are added to the mixture, and the mixture is stirred at room temperature for 5 hours. The reaction mixture is poured into 100 ml of water, and crystalline precipitates are collected by filtration. The crystals are dissolved in ethyl acetate, and the solution is washed with water and then dried. The solution is concentrated under reduced pressure to remove solvent. Then, the residue is crystallized with isopropyl ether and collected by filtration. 2.1 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(1-methyl-2-pyrrolidon-3-yl)oxyimino]acetate are obtained. the mixture is stirred at room temperature for 5 hours crystalline precipitates are collected by filtration The crystals are dissolved in ethyl acetate the solution is washed with water dried The solution is concentrated under reduced pressure to remove solvent Then, the residue is crystallized with isopropyl ether collected by filtration

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

Procedure: 2.7 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2hydroxyiminoacetate are dissolved in 12 ml of dimethylsulfoxide, and 1.0 g of anhydrous potassium carbonate is added thereto under nitrogen gas atmosphere. The mixture is stirred at room temperature for 10 minutes. 1.2 g of 1-methyl-3-bromo-2-pyrrolidone are added to the mixture, and the mixture is stirred at room temperature for 5 hours. The reaction mixture is poured into 100 ml of water, and crystalline precipitates are collected by filtration. The crystals are dissolved in ethyl acetate, and the solution is washed with water and then dried. The solution is concentrated under reduced pressure to remove solvent. Then, the residue is crystallized with isopropyl ether and collected by filtration. 2.1 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(1-methyl-2-pyrrolidon-3-yl)oxyimino]acetate are obtained. the mixture is stirred at room temperature for 5 hours crystalline precipitates are collected by filtration The crystals are dissolved in ethyl acetate the solution is washed with water dried The solution is concentrated under reduced pressure to remove solvent Then, the residue is crystallized with isopropyl ether collected by filtration

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

Procedure: 2.7 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-hydroxyiminoacetate are dissolved in 12 ml of dimethylsulfoxide, and 1.0 g of anhydrous potassium carbonate is added thereto under nitrogen gas atmosphere. The mixture is stirred at room temperature for 10 minutes. 1.2 g of 1-methyl-3-bromo-2-pyrrolidone are added to the mixture, and the mixture is stirred at room temperature for 5 hours. The reaction mixture is poured into 100 ml of water, and crystalline precipitates are collected by filtration. The crystals are dissolved in ethyl acetate, and the solution is washed with water and then dried. The solution is concentrated under reduced pressure to remove solvent. Then, the residue is crystallized with isopropyl ether and collected by filtration. 2.1 g of ethyl (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(1-methyl-2-pyrrolidon-3-yl)oxyimino]acetate are obtained. the mixture is stirred at room temperature for 5 hours crystalline precipitates are collected by filtration The crystals are dissolved in ethyl acetate the solution is washed with water dried The solution is concentrated under reduced pressure to remove solvent Then, the residue is crystallized with isopropyl ether collected by filtration

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

Procedure: Methyl 3-hydroxy-5-phenylmethoxy-benzoate (CAS no. 54915-31-0) (10.3 g, 40 mmol) and 3-bromo-1-methyl-pyrrolidin-2-one (Intermediate 4) (8.54 g, 48 mmol) were dissolved in DMF and treated with potassium carbonate (12.1 g, 88 mmol) and stirred at room temperature for 16 hours and then at 50° C. for 3 hours. The DMF was evaporated under reduced pressure and the residue partitioned between ethyl acetate (100 mL) and water (30 mL). The organic layer was separated, washed with brine (30 mL), dried (MgSO4) and evaporated under reduced pressure. The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane to give the racemic product (8.7 g). The desired product was separated from its enantiomer by chiral HPLC using Merck 50 mm 20 μm Chiralpak AS—No ASV00SC JG001 and ASV000SC BD004 columns in series, eluting with 30% ethylacetate in isohexane at a flow rate of 60 mL/min, using 9 separate injections of 70 mL of a 14 mg/ml solution of the racemate in Ethanol (32 mL) and isohexane (38 mL) to afford the product (3.6 g, 41%) which eluted after its enantiomer. 1H NMR δ (300 MHz, CDCl3) 2.06-2.20 (m, 1H), 2.51-2.63 (m, 1H), 2.94 (s, 3H), 3.31-3.54 (m, 2H), 3.89 (s, 3H), 4.87 (t, 1H), 5.08 (s, 2H), 6.90 (t, 1H), 7.27-7.46 (m, 7H). at 50° C. for 3 hours The DMF was evaporated under reduced pressure the residue partitioned between ethyl acetate (100 mL) and water (30 mL) The organic layer was separated washed with brine (30 mL) dried (MgSO4) evaporated under reduced pressure The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane

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

Procedure: Methyl 3-hydroxy-5-phenylmethoxy-benzoate (CAS no. 54915-31-0) (10.3 g, 40 mmol) and 3-bromo-1-methyl-pyrrolidin-2-one (Intermediate 4) (8.54 g, 48 mmol) were dissolved in DMF, treated with potassium carbonate (12.1 g, 88 mmol) and stirred at room temperature for 16 hours and then at 50° C. for 3 hours. The DMF was evaporated under reduced pressure and the residue partitioned between ethyl acetate (100 mL) and water (30 mL). The organic layer was separated, washed with brine (30 mL), dried (MgSO4) and evaporated under reduced pressure. The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane to give the racemic product (8.7 g). The desired product was separated from its enantiomer by chiral HPLC using Merck 50 mm 20 μm Chiralpak AS—No ASV00SC JG001 and ASV000SC BD004 columns in series, eluting with 30% ethylacetate in isohexane at a flow rate of 60 mL/min, using 9 separate injections of 70 mL of a 14 mg/ml solution of the racemate in ethanol (32 mL) and isohexane (38 mL) to afford the product (3.6 g, 41%) which eluted before its enantiomer. 1H NMR δ (300 MHz, CDCl3) 2.06-2.20 (m, 1H), 2.51-2.63 (m, 1H), 2.94 (s, 3H), 3.31-3.54 (m, 2H), 3.89 (s, 3H), 4.87 (t, 1H), 5.08 (s, 2H), 6.90 (t, 1H), 7.27-7.46 (m, 7H). at 50° C. for 3 hours The DMF was evaporated under reduced pressure the residue partitioned between ethyl acetate (100 mL) and water (30 mL) The organic layer was separated washed with brine (30 mL) dried (MgSO4) evaporated under reduced pressure The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane

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

Procedure: Methyl 3-hydroxy-5-phenylmethoxy-benzoate (CAS no. 54915-31-0) (10.3 g, 40 mmol) and 3-bromo-1-methyl-pyrrolidin-2-one (Intermediate 4) (8.54 g, 48 mmol) were dissolved in DMF, treated with potassium carbonate (12.1 g, 88 mmol) and stirred at room temperature for 16 hours and then at 50° C. for 3 hours. The DMF was evaporated under reduced pressure and the residue partitioned between ethyl acetate (100 mL) and water (30 mL). The organic layer was separated, washed with brine (30 mL), dried (MgSO4) and evaporated under reduced pressure. The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane to give the racemic product (8.7 g). The desired product was separated from its enantiomer by chiral HPLC using Merck 50 mm 20 μm Chiralpak AS—No ASV00SC JG001 and ASV000SC BD004 columns in series, eluting with 30% ethylacetate in isohexane at a flow rate of 60 mL/min, using 9 separate injections of 70 mL of a 14 mg/ml solution of the racemate in ethanol (32 mL) and isohexane (38 mL) to afford the product (3.6 g, 41%) which eluted before its enantiomer. 1H NMR δ (300 MHz, CDCl3) 2.06-2.20 (m, 1H), 2.51-2.63 (m, 1H), 2.94 (s, 3H), 3.31-3.54 (m, 2H), 3.89 (s, 3H), 4.87 (t, 1H), 5.08 (s, 2H), 6.90 (t, 1H), 7.27-7.46 (m, 7H). at 50° C. for 3 hours The DMF was evaporated under reduced pressure the residue partitioned between ethyl acetate (100 mL) and water (30 mL) The organic layer was separated washed with brine (30 mL) dried (MgSO4) evaporated under reduced pressure The residue was purified by flash chromatography on silica eluting with 0-100% ethyl acetate in hexane