2-butylsulfanylcarbothioylsulfanylpropanoic acid

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

Procedure: Dodecanethiol (2.50 g, 12.5 mmol), acetone (40 mL), and tetrapropylammonium bromide (0.27 g, 0.10 mmol) were added to a solution of sodium hydroxide (0.50 g, 12.5 mmol) in water (5 mL). The resulting solution was cooled in an ice bath and treated with carbon disulfide (0.75 mL, 0.95 g, 12.5 mmol). After 20 min, 2-bromopropanoic acid (1.91 g, 12.5 mmol) was added and the mixture was stirred at ambient temperature for 12 h. The solution was evaporated to ¼ volume and slowly acidified with 2 M hydrochloric acid (50 mL), then further diluted with water (150 mL). The resulting solid was collected and recrystallised from ether/light petroleum to give the title compound (15, R3=C12H25) as yellow crystals (3.33 g, 76%). The resulting solution was cooled in an ice bath The solution was evaporated further diluted with water (150 mL) The resulting solid was collected recrystallised from ether/light petroleum

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

Procedure: Acetone (700 mL) and tetrapropylammonium bromide (5.58 g, 21.0 mmol) were added with stirring to a solution of sodium hydroxide (10.5 g, 0.263 mol) in water (36 mL), followed by 1-butanethiol (23.7 g, 0.263 mol). After 20 min, carbon disulfide (17 mL, 21.7 g, 0.285 mol) was added and stirring was continued for 15 min, after which 2-bromopropanoic acid (40.14 g, 0.263 mol) was added. The reaction was stirred overnight, then acidified to pH<1 with 2 M hydrochloric acid (100 mL). The acetone was removed under reduced pressure and the remaining mixture was extracted with ether (400 mL). The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL), dried (sodium sulfate), and evaporated. The oily residue was crystallized by the addition of ice (500 g), the crystals were collected by filtration and washed with water (5×100 mL) and then dried in a vacuum oven at room temperature. The resulting impure product was redissolved in ether (400 mL) and extracted with saturated sodium bicarbonate (5×150 mL). The combined aqueous extracts were acidified to pH<1 with concentrated hydrochloric acid and extracted with ether (400 mL). The organic extract was washed with saturated sodium chloride (200 mL), dried (sodium sulfate), and evaporated under reduced pressure. The residue was crystallized by the addition of ice (500 g) and the solid was collected and washed with water (5×1 50 mL), then dried in a vacuum oven to give the title compound (15, R3=C4H9) as a yellow solid (39.0 g, 62%). was continued for 15 min The reaction was stirred overnight The acetone was removed under reduced pressure the remaining mixture was extracted with ether (400 mL) The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL) dried (sodium sulfate) evaporated The oily residue was crystallized by the addition of ice (500 g) the crystals were collected by filtration washed with water (5×100 mL) dried in a vacuum oven at room temperature The resulting impure product was redissolved in ether (400 mL) extracted with saturated sodium bicarbonate (5×150 mL) extracted with ether (400 mL) The organic extract was washed with saturated sodium chloride (200 mL) dried (sodium sulfate) evaporated under reduced pressure The residue was crystallized by the addition of ice (500 g) the solid was collected washed with water (5×1 50 mL) dried in a vacuum oven

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

Procedure: Dodecanethiol (2.50 g, 12.5 mmol), acetone (40 mL), and tetrapropylammonium bromide (0.27 g, 0.10 mmol) were added to a solution of sodium hydroxide (0.50 g, 12.5 mmol) in water (5 mL). The resulting solution was cooled in an ice bath and treated with carbon disulfide (0.75 mL, 0.95 g, 12.5 mmol). After 20 min, 2-bromopropanoic acid (1.91 g, 12.5 mmol) was added and the mixture was stirred at ambient temperature for 12 h. The solution was evaporated to ¼ volume and slowly acidified with 2 M hydrochloric acid (50 mL), then further diluted with water (150 mL). The resulting solid was collected and recrystallised from ether/light petroleum to give the title compound (15, R3=C12H25) as yellow crystals (3.33 g, 76%). The resulting solution was cooled in an ice bath The solution was evaporated further diluted with water (150 mL) The resulting solid was collected recrystallised from ether/light petroleum

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

Procedure: Acetone (700 mL) and tetrapropylammonium bromide (5.58 g, 21.0 mmol) were added with stirring to a solution of sodium hydroxide (10.5 g, 0.263 mol) in water (36 mL), followed by 1-butanethiol (23.7 g, 0.263 mol). After 20 min, carbon disulfide (17 mL, 21.7 g, 0.285 mol) was added and stirring was continued for 15 min, after which 2-bromopropanoic acid (40.14 g, 0.263 mol) was added. The reaction was stirred overnight, then acidified to pH<1 with 2 M hydrochloric acid (100 mL). The acetone was removed under reduced pressure and the remaining mixture was extracted with ether (400 mL). The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL), dried (sodium sulfate), and evaporated. The oily residue was crystallized by the addition of ice (500 g), the crystals were collected by filtration and washed with water (5×100 mL) and then dried in a vacuum oven at room temperature. The resulting impure product was redissolved in ether (400 mL) and extracted with saturated sodium bicarbonate (5×150 mL). The combined aqueous extracts were acidified to pH<1 with concentrated hydrochloric acid and extracted with ether (400 mL). The organic extract was washed with saturated sodium chloride (200 mL), dried (sodium sulfate), and evaporated under reduced pressure. The residue was crystallized by the addition of ice (500 g) and the solid was collected and washed with water (5×1 50 mL), then dried in a vacuum oven to give the title compound (15, R3=C4H9) as a yellow solid (39.0 g, 62%). was continued for 15 min The reaction was stirred overnight The acetone was removed under reduced pressure the remaining mixture was extracted with ether (400 mL) The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL) dried (sodium sulfate) evaporated The oily residue was crystallized by the addition of ice (500 g) the crystals were collected by filtration washed with water (5×100 mL) dried in a vacuum oven at room temperature The resulting impure product was redissolved in ether (400 mL) extracted with saturated sodium bicarbonate (5×150 mL) extracted with ether (400 mL) The organic extract was washed with saturated sodium chloride (200 mL) dried (sodium sulfate) evaporated under reduced pressure The residue was crystallized by the addition of ice (500 g) the solid was collected washed with water (5×1 50 mL) dried in a vacuum oven

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

Procedure: Dodecanethiol (2.50 g, 12.5 mmol), acetone (40 mL), and tetrapropylammonium bromide (0.27 g, 0.10 mmol) were added to a solution of sodium hydroxide (0.50 g, 12.5 mmol) in water (5 mL). The resulting solution was cooled in an ice bath and treated with carbon disulfide (0.75 mL, 0.95 g, 12.5 mmol). After 20 min, 2-bromopropanoic acid (1.91 g, 12.5 mmol) was added and the mixture was stirred at ambient temperature for 12 h. The solution was evaporated to ¼ volume and slowly acidified with 2 M hydrochloric acid (50 mL), then further diluted with water (150 mL). The resulting solid was collected and recrystallised from ether/light petroleum to give the title compound (15, R3=C12H25) as yellow crystals (3.33 g, 76%). The resulting solution was cooled in an ice bath The solution was evaporated further diluted with water (150 mL) The resulting solid was collected recrystallised from ether/light petroleum

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

Procedure: Acetone (700 mL) and tetrapropylammonium bromide (5.58 g, 21.0 mmol) were added with stirring to a solution of sodium hydroxide (10.5 g, 0.263 mol) in water (36 mL), followed by 1-butanethiol (23.7 g, 0.263 mol). After 20 min, carbon disulfide (17 mL, 21.7 g, 0.285 mol) was added and stirring was continued for 15 min, after which 2-bromopropanoic acid (40.14 g, 0.263 mol) was added. The reaction was stirred overnight, then acidified to pH<1 with 2 M hydrochloric acid (100 mL). The acetone was removed under reduced pressure and the remaining mixture was extracted with ether (400 mL). The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL), dried (sodium sulfate), and evaporated. The oily residue was crystallized by the addition of ice (500 g), the crystals were collected by filtration and washed with water (5×100 mL) and then dried in a vacuum oven at room temperature. The resulting impure product was redissolved in ether (400 mL) and extracted with saturated sodium bicarbonate (5×150 mL). The combined aqueous extracts were acidified to pH<1 with concentrated hydrochloric acid and extracted with ether (400 mL). The organic extract was washed with saturated sodium chloride (200 mL), dried (sodium sulfate), and evaporated under reduced pressure. The residue was crystallized by the addition of ice (500 g) and the solid was collected and washed with water (5×1 50 mL), then dried in a vacuum oven to give the title compound (15, R3=C4H9) as a yellow solid (39.0 g, 62%). was continued for 15 min The reaction was stirred overnight The acetone was removed under reduced pressure the remaining mixture was extracted with ether (400 mL) The extract was washed with water (2×100 mL), saturated sodium chloride solution (200 mL) dried (sodium sulfate) evaporated The oily residue was crystallized by the addition of ice (500 g) the crystals were collected by filtration washed with water (5×100 mL) dried in a vacuum oven at room temperature The resulting impure product was redissolved in ether (400 mL) extracted with saturated sodium bicarbonate (5×150 mL) extracted with ether (400 mL) The organic extract was washed with saturated sodium chloride (200 mL) dried (sodium sulfate) evaporated under reduced pressure The residue was crystallized by the addition of ice (500 g) the solid was collected washed with water (5×1 50 mL) dried in a vacuum oven