1,3-thiazolidin-4-one

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

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

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

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

Procedure: To a stirred solution of 10.3 g of 4-oxothiazolidine in 500 ml of anhydrous dimethylformamide under N2 was added 6.0 g of sodium hydride (50% in oil). After 30 min., 15 ml of a solution of 80% propargyl bromide in toluene was added and the mixture was allowed to stir for another hour. The mixture was then poured into saturated aqueous sodium bicarbonate and extracted with ethyl acetate. The combined organic fractions were washed twice with water, then once with brine, dried (MgSO4), filtered and concentrated. The residue was distilled at 0.1/mm Hg, 95°-98° C., to provide 9.248 g of 3-propargyl-4-oxothiazolidine as an oil which solidified upon refrigeration, mp 29°-31°. extracted with ethyl acetate The combined organic fractions were washed twice with water once with brine, dried (MgSO4) filtered concentrated The residue was distilled at 0.1/mm Hg, 95°-98° C.

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

Procedure: A mixture of 4-thiazolidinone (25 g), dimethylformamide (DMF hereafter, 500 ml) and KOH (27.16 g) was stirred under N2 at room temperature for 1.5 h. To the resulting mixture was added 1,4-dibromobutane (101 ml), which rapidly caused the reaction mixture to turn milky white. Stirring was continued at room temperature for 44 h. The reaction mixture was poured into H2O (1000 ml) and the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter, 3×300 ml). The combined extracts were washed successively with H2O (300 ml) and brine (300 ml), dried over Na2SO4, and concentrated in vacuo to an amber oil. HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg. the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter The combined extracts were washed successively with H2O (300 ml) and brine (300 ml) dried over Na2SO4 concentrated in vacuo to an amber oil HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg

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

Procedure: A mixture of 4-thiazolidinone (25 g), dimethylformamide (DMF hereafter, 500 ml) and KOH (27.16 g) was stirred under N2 at room temperature for 1.5 h. To the resulting mixture was added 1,4-dibromobutane (101 ml), which rapidly caused the reaction mixture to turn milky white. Stirring was continued at room temperature for 44 h. The reaction mixture was poured into H2O (1000 ml) and the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter, 3×300 ml). The combined extracts were washed successively with H2O (300 ml) and brine (300 ml), dried over Na2SO4, and concentrated in vacuo to an amber oil. HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg. the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter The combined extracts were washed successively with H2O (300 ml) and brine (300 ml) dried over Na2SO4 concentrated in vacuo to an amber oil HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg

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

Procedure: A mixture of 4-thiazolidinone (25 g), dimethylformamide (DMF hereafter, 500 ml) and KOH (27.16 g) was stirred under N2 at room temperature for 1.5 h. To the resulting mixture was added 1,4-dibromobutane (101 ml), which rapidly caused the reaction mixture to turn milky white. Stirring was continued at room temperature for 44 h. The reaction mixture was poured into H2O (1000 ml) and the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter, 3×300 ml). the combined extracts were washed successively with H2O (300 ml) and brine (300 ml), dried over Na2SO4, and concentrated in vacuo to an amber oil. HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg. the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter the combined extracts were washed successively with H2O (300 ml) and brine (300 ml) dried over Na2SO4 concentrated in vacuo to an amber oil HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg

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

Procedure: A mixture of 4-thiazolidinone (25 g), dimethylformamide (DMF hereafter, 500 ml) and KOH (27.16 g) was stirred under N2 at room temperature for 1.5 h. To the resulting mixture was added 1,4-dibromobutane (101 ml), which rapidly caused the reaction mixture to turn milky white. Stirring was continued at room temperature for 44 h. The reaction mixture was poured into H2O (1000 ml) and the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter, 3×300 ml). the combined extracts were washed successively with H2O (300 ml) and brine (300 ml), dried over Na2SO4, and concentrated in vacuo to an amber oil. HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg. the aqueous mixture was extracted with ethyl acetate (EtOAc hereafter the combined extracts were washed successively with H2O (300 ml) and brine (300 ml) dried over Na2SO4 concentrated in vacuo to an amber oil HPLC (high performance liquid chromatography) of a 44.95 g aliquot yielded 7.15 g of an oil which upon distillation yielded a clear liquid, b.p. 134°-137° C./0.12 mm Hg

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

Procedure: Sodium hydride (60% dispersion in mineral oil) (0.58 g) was added portionwise to a solution of 4-oxothiazolidine (1.50 g) and 4-methoxybenzenesulfonyl chloride (3.01 g) in tetrahydrofuran (30 ml) at 0° C. with stirring and the mixture was stirred for 1 hour at the same temperature. After the solvent was evaporated in vacuo, the residue was mixed with ethyl acetate (10 ml) and water (50 ml) and the resultant precipitate was collected by filtration. The cake was washed with water and diisopropyl ether and recrystallized from a mixture of ethanol and ethyl acetate to give 3-(4-methoxybenzenesulfonyl)-4-oxothiazolidine (1.65 g) as slightly brown prisms. the mixture was stirred for 1 hour at the same temperature After the solvent was evaporated in vacuo the residue was mixed with ethyl acetate (10 ml) and water (50 ml) the resultant precipitate was collected by filtration The cake was washed with water and diisopropyl ether recrystallized from a mixture of ethanol and ethyl acetate

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

Procedure: A solution of 4-methoxybenzoyl chloride (20.7 g) in tetrahydrofuran (50 ml) was added dropwise to a mixture of 4-oxo-thiazolidine (12.5 g) and triethylamine (16.9 ml) in tetrahydrofuran (200 ml) at -5° C. with stirring. The mixture was stirred at that temperature for 3 hours and at room temperature for 4 hours, and allowed to stand overnight. After the solvent was evaporated in vacuo, the residue was mixed with water and extracted with ethyl acetate. The extract was washed with saturated aqueous sodium hydrogen carbonate and then with water, dried over magnesium sulfate and evaporated in vacuo. The residue was recrystallized from a mixture of ethyl acetate and n-hexane to give 3-(4-methoxybenzoyl)-4-oxothiazolidine (18.1 g) as slightly brown prisms. The mixture was stirred at that temperature for 3 hours and at room temperature for 4 hours After the solvent was evaporated in vacuo the residue was mixed with water extracted with ethyl acetate The extract was washed with saturated aqueous sodium hydrogen carbonate with water, dried over magnesium sulfate evaporated in vacuo The residue was recrystallized from a mixture of ethyl acetate and n-hexane

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

Procedure: A solution of 4-oxothiazolidine (3.00 g) in tetrahydrofuran (40 ml) was added dropwise to a suspension of sodium hydride (60% dispersion in mineral oil) (1.28 g) in tetrahydrofuran (30 ml) at room temperature with stirring. 3-Bromo-1-chloropropane (3.15 ml) was added dropwise to the mixture under refluxing and the mixture was allowed to reflux for 9 hours. After the resultant precipitate was removed by filtration, the filtrate was evaporated in vacuo. The residue was chromatographed on basic alumina by eluting with ethyl acetate and then with a 10:1 mixture of toluene and ethyl acetate to give 3-(3-chloropropyl)-4-oxothiazolidine (2.60 g) as colorless oil. under refluxing to reflux for 9 hours After the resultant precipitate was removed by filtration the filtrate was evaporated in vacuo The residue was chromatographed on basic alumina by eluting with ethyl acetate with a 10:1 mixture of toluene and ethyl acetate

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

Procedure: A solution of 4-oxothiazolidine (50 g) in tetrahydrofuran (900 ml) was added dropwise to a suspension of sodium hydride (60% dispersion in mineral oil) (22.6 g) in tetrahydrofuran (850 ml) at room temperature and the mixture was allowed to warm up to reflux temperature. After the mixture was refluxed for an additional 30 minutes, ethyl bromoacetate (60 ml) was added dropwise under that condition. The mixture was refluxed further 1 hour and then cooled. Insoluble materials were removed by filtration. The filtrate was evaporated in vacuo and the residue was purified by silica gel column chromatography by eluting with chloroform to give ethyl 4-oxo-3-thiazolidinylacetate (78.5 g) as light brown powder. to warm up to reflux temperature After the mixture was refluxed for an additional 30 minutes The mixture was refluxed further 1 hour cooled Insoluble materials were removed by filtration The filtrate was evaporated in vacuo the residue was purified by silica gel column chromatography by eluting with chloroform