Carbon Disulfide → (2-Sulfanylidene-2,3-dihydro-1,3-benzothiazol-5-yl)acetic acid

HRID 1595164Notes

Reaction equation

HRID 1595164 reaction equation
Cl[C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]([OH:11])=[O:10])=[CH:4][C:3]=1[N+:12]([O-])=O.[OH-].[Na+].[C:17](=[S:19])=[S:18].C(=O)([O-])[O-].[Na+].[Na+]>O.C(O)(=O)C>[C:9]([CH2:8][C:5]1[CH:6]=[CH:7][C:2]2[S:19][C:17](=[S:18])[NH:12][C:3]=2[CH:4]=1)([OH:11])=[O:10]

Participants

7

Reactant 4

HCID 6348Carbon DisulfideHCID 10340Sodium CarbonateHCID 14798Sodium HydroxideHCID 15019094-Chloro-3-nitrophenylacetic Acid

Product 1

HCID 21703647(2-Sulfanylidene-2,3-dihydro-1,3-benzothiazol-5-yl)acetic acidYield 54.3%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Conditions

Temperature
115 °C

Procedure

A solution of 4-chloro-3-nitro-phenylacetic acid (25.0 g, 0.116 mol) in 1N aqueous NaOH (143 mL, 0.143 mol) was added to preformed polysulfide solution (from 72.42 g, 0.301 mol of Na2S.9H2O, 26.87 g, 0.837 mol of S, and 74 mL of H2O) at 50° C. The resulting mixture was mechanically stirred as the temperature of the oil bath was gradually increased to 115° C. over 10 min. The mixture was stirred at that temperature for two hours then allowed to cool to room temperature over two hours. Carbon disulfide (13.9 mL, 0.231 mol) was added and the reaction flask was placed in a 50° C. oil bath. The reaction mixture was stirred at that temperature for 18 hours then cooled in an ice bath, stirred, and acidified by cautious addition of glacial acetic acid (50 mL). The mixture was filtered and the filter cake was washed with water. The solid was stirred with sodium carbonate (30.7 g, 0.29 mol) in water then filtered to remove sulfur. The filtrate was cooled in an ice-bath and gradually acidified to pH 3.3 by addition of 6N HCl (100 mL). The precipitate was collected, washed with ice-cold water (100 mL) and dried in vacuo to a pale brown solid (21.5 g, 82%). This crude product was recrystallized from ethanol to afford 5-carboxymethyl-2-thioxo-2,3-dihydrobenzothiazole as a pale brown solid (14.2 g).

Workup

  1. stirringThe mixture was stirred at that temperature for two hours
  2. temperatureto cool to room temperature over two hours
  3. customwas placed in a 50° C.
  4. stirringThe reaction mixture was stirred at that temperature for 18 hours
  5. temperaturethen cooled in an ice bath
  6. stirringstirred
  7. filtrationThe mixture was filtered
  8. washthe filter cake was washed with water
  9. filtrationthen filtered
  10. customto remove sulfur
  11. temperatureThe filtrate was cooled in an ice-bath
  12. additiongradually acidified to pH 3.3 by addition of 6N HCl (100 mL)
  13. customThe precipitate was collected
  14. washwashed with ice-cold water (100 mL)
  15. dry with materialdried in vacuo to a pale brown solid (21.5 g, 82%)
  16. customThis crude product was recrystallized from ethanol

Sources & evidence

ORD record
ord-1c8d6ea677f54a55a8145f1f3224afc7
Source dataset
uspto-grants-2001_09
Patent number
US06288054B1

Reaction notes

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