methyl 2-methylsulfonylacetate

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

Procedure: To a solution of methyl methylsulfonylacetate (1.0 g, 6.6 mmol) in 20 mL of acetonitrile was added 1,3-diiodopropane (2.3 mL, 20 mmol) and cesium carbonate (6.4 g, 20 mmol). After stirring at room temperature for 2 h, the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL). The organic layer was separated, dried over anhydrous magnesium sulfate, filtered and concentrated to dryness, and the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane to give methyl 1-methylsulfonylcyclobutanecarboxlate (1.0 g, 79%). δ 3.84 (s, 3H), 3.02 (s, 3H), 2.84-2.65 (m, 4H), 2.25-2.02 (m, 2H). the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL) The organic layer was separated dried over anhydrous magnesium sulfate filtered concentrated to dryness the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane

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

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

Procedure: To a suspension of dimethyl sulfone (5.43 g) in tetrahydrofuran (10 mL) was addded 1.59 M n-butyl lithium (36.3 mL) in a dryice-acetone bath under a nitrogen atmosphere. After stirring for 0.5 hour, a solution of methyl methoxyacetate (2.00 g) in tetrahydrofuran (5 mL) was added. The resulting mixture was stirred for 2 hours in the bath and allowed to warm to room temperature over 2 hours. The mixture was partitioned between EtOAc and 4 N hydrochloric acid. The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL). The mixture was partitioned between EtOAc (100 mL) and brine (100 mL). The aqueous layer was washed with EtOAc (100 mL, five times). The organic layer was combined, and the combined extracts were dried over MgSO4, and evaporated. Flash silicagel column chromatography (EtOAc-hexane=50-200 to 300-100) afforded 2-(methylsulfonyl)-1-methoxyethanone as a colorless oil (2.24 g). The resulting mixture was stirred for 2 hours in the bath The mixture was partitioned between EtOAc and 4 N hydrochloric acid The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL) The mixture was partitioned between EtOAc (100 mL) and brine (100 mL) The aqueous layer was washed with EtOAc (100 mL, five times) the combined extracts were dried over MgSO4 evaporated

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

Procedure: To a suspension of dimethyl sulfone (5.43 g) in tetrahydrofuran (10 mL) was addded 1.59 M n-butyl lithium (36.3 mL) in a dryice-acetone bath under a nitrogen atmosphere. After stirring for 0.5 hour, a solution of methyl methoxyacetate (2.00 g) in tetrahydrofuran (5 mL) was added. The resulting mixture was stirred for 2 hours in the bath and allowed to warm to room temperature over 2 hours. The mixture was partitioned between EtOAc and 4 N hydrochloric acid. The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL). The mixture was partitioned between EtOAc (100 mL) and brine (100 mL). The aqueous layer was washed with EtOAc (100 mL, five times). The organic layer was combined, and the combined extracts were dried over MgSO4, and evaporated. Flash silicagel column chromatography (EtOAc-hexane=50-200 to 300-100) afforded 2-(methylsulfonyl)-1-methoxyethanone as a colorless oil (2.24 g). The resulting mixture was stirred for 2 hours in the bath The mixture was partitioned between EtOAc and 4 N hydrochloric acid The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL) The mixture was partitioned between EtOAc (100 mL) and brine (100 mL) The aqueous layer was washed with EtOAc (100 mL, five times) the combined extracts were dried over MgSO4 evaporated

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 15.2 g of methyl methylsulfonylacetate, 7.6 g of carbon disulfide and 200 ml of dimethylformamide, 14.0 g of potassium hydroxide was added under ice-cooling. The resultant mixture was stirred for 3 hours. Thereafter, 9.7 g of cis-1,2-dichloroethylene was added, followed by stirring at 80° C. for 4 hours. After cooling the reaction mixture, chloroform and water were added and the resulting organic layer was separated. Upon removal of the solvent by distillation under reduced pressure, 20.9 g of the title compound was obtained as pale yellow crystals. Upon recrystallization from a mixed solvent of chloroform and n-hexane, they turned to white crystals. Melting point: 166°-168° C. (decomposed). was added under ice- cooling were added the resulting organic layer was separated Upon removal of the solvent by distillation under reduced pressure

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

Procedure: To a solution of methyl methylsulfonylacetate (1.0 g, 6.6 mmol) in 20 mL of acetonitrile was added 1,3-diiodopropane (2.3 mL, 20 mmol) and cesium carbonate (6.4 g, 20 mmol). After stirring at room temperature for 2 h, the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL). The organic layer was separated, dried over anhydrous magnesium sulfate, filtered and concentrated to dryness, and the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane to give methyl 1-methylsulfonylcyclobutanecarboxlate (1.0 g, 79%). δ 3.84 (s, 3H), 3.02 (s, 3H), 2.84-2.65 (m, 4H), 2.25-2.02 (m, 2H). the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL) The organic layer was separated dried over anhydrous magnesium sulfate filtered concentrated to dryness the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane

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

Procedure: To a solution of methyl methylsulfonylacetate (1.0 g, 6.6 mmol) in 20 mL of acetonitrile was added 1,3-diiodopropane (2.3 mL, 20 mmol) and cesium carbonate (6.4 g, 20 mmol). After stirring at room temperature for 2 h, the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL). The organic layer was separated, dried over anhydrous magnesium sulfate, filtered and concentrated to dryness, and the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane to give methyl 1-methylsulfonylcyclobutanecarboxlate (1.0 g, 79%). δ 3.84 (s, 3H), 3.02 (s, 3H), 2.84-2.65 (m, 4H), 2.25-2.02 (m, 2H). the reaction was partitioned between water (50 mL) and ethyl acetate (100 mL) The organic layer was separated dried over anhydrous magnesium sulfate filtered concentrated to dryness the residue was purified by flash chromatography on silica gel eluting with 20 to 50% ethyl acetate in hexane

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

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

Procedure: To a suspension of dimethyl sulfone (5.43 g) in tetrahydrofuran (10 mL) was added 1.59 M n-butyl lithium (36.3 mL) in a dryice-acetone bath under a nitrogen atmosphere. After stirring for 0.5 hour, a solution of methyl methoxyacetate (2.00 g) in tetrahydrofuran (5 mL) was added. The resulting mixture was stirred for 2 hours in the bath and allowed to warm to room temperature over 2 hours. The mixture was partitioned between EtOAc and 4 N hydrochloric acid. The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL). The mixture was partitioned between EtOAc (100 mL) and brine (100 mL). The aqueous layer was washed with EtOAc (100 mL, five times). The organic layer was combined, and the combined extracts were dried over MgSO4, and evaporated. Flash silica gel column chromatography (EtOAc-hexane=50-200 to 300-100) afforded 2-(methylsulfonyl)-1-methoxyethanone as a colorless oil (2.24 g). The resulting mixture was stirred for 2 hours in the bath The mixture was partitioned between EtOAc and 4 N hydrochloric acid The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL) The mixture was partitioned between EtOAc (100 mL) and brine (100 mL) The aqueous layer was washed with EtOAc (100 mL, five times) the combined extracts were dried over MgSO4 evaporated

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

Procedure: To a suspension of dimethyl sulfone (5.43 g) in tetrahydrofuran (10 mL) was addded 1.59 M n-butyl lithium (36.3 mL) in a dryice-acetone bath under a nitrogen atmosphere. After stirring for 0.5 hour, a solution of methyl methoxyacetate (2.00 g) in tetrahydrofuran (5 mL) was added. The resulting mixture was stirred for 2 hours in the bath and allowed to warm to room temperature over 2 hours. The mixture was partitioned between EtOAc and 4 N hydrochloric acid. The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL). The mixture was partitioned between EtOAc (100 mL) and brine (100 mL). The aqueous layer was washed with EtOAc (100 mL, five times). The organic layer was combined, and the combined extracts were dried over MgSO4, and evaporated. Flash silicagel column chromatography (EtOAc-hexane=50-200 to 300-100) afforded 2-(methylsulfonyl)-1-methoxyethanone as a colorless oil (2.24 g). The resulting mixture was stirred for 2 hours in the bath The mixture was partitioned between EtOAc and 4 N hydrochloric acid The reaction was quenched by adding 4 N hydrochloric acid in EtOAc (15 mL) The mixture was partitioned between EtOAc (100 mL) and brine (100 mL) The aqueous layer was washed with EtOAc (100 mL, five times) the combined extracts were dried over MgSO4 evaporated

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 15.2 g of methyl methylsulfonylacetate, 7.6 g of carbon disulfide and 200 ml of dimethylformamide, 14.0 g of potassium hydroxide was added under ice-cooling. The resultant mixture was stirred for 3 hours. Thereafter, 9.7 g of cis-1,2-dichloroethylene was added, followed by stirring at 80° C. for 4 hours. After cooling the reaction mixture, chloroform and water were added and the resulting organic layer was separated. Upon removal of the solvent by distillation under reduced pressure, 20.9 g of the title compound was obtained as pale yellow crystals. Upon recrystallization from a mixed solvent of chloroform and n-hexane, they turned to white crystals. Melting point: 166°-168° C. (decomposed). was added under ice- cooling were added the resulting organic layer was separated Upon removal of the solvent by distillation under reduced pressure