Methyl chloroacetate → 3-Oxo-naphth[2,1-d]isothiazoline-2-acetic acid methyl ester-1,1-dioxide

HRID 1730531Notes

Reaction equation

HRID 1730531 reaction equation
[O:1]=[C:2]1[C:6]2[CH:7]=[CH:8][C:9]3[C:14]([C:5]=2[S:4](=[O:16])(=[O:15])[NH:3]1)=[CH:13][CH:12]=[CH:11][CH:10]=3.[Na].Cl[CH2:19][C:20]([O:22][CH3:23])=[O:21]>CO>[CH3:23][O:22][C:20](=[O:21])[CH2:19][N:3]1[C:2](=[O:1])[C:6]2[CH:7]=[CH:8][C:9]3[C:14]([C:5]=2[S:4]1(=[O:16])=[O:15])=[CH:13][CH:12]=[CH:11][CH:10]=3

Participants

5

Reactant 3

HCID 7295Methyl chloroacetateHCID 5360545SodiumHCID 124215141H-1lambda~6~-Naphtho[2,1-d][1,2]thiazole-1,1,3(2H)-trione

Product 1

HCID 105426033-Oxo-naphth[2,1-d]isothiazoline-2-acetic acid methyl ester-1,1-dioxideYield 98.3%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

70.0 gm (0.30 mol) of 3-oxo-naphth[2,1-d]isothiazoline-1,1-dioxide were added to a solution of 7.82 gm (0.34 gm-atom) of sodium in 300 ml of absolute methanol. The majority of the alcohol was subsequently distilled off, and the residual sodium salt of 3-oxo-naphth[2,1-d]isothiazoline-1,1-dioxide was dissolved in 100 ml of absolute dimethylsulfoxide. At a temperature of 50° C, 43.41 gm (0.40 mol) of methyl chloroacetate were added dropwise to this solution. The resulting mixture was stirred at room temperature for half an hour, then slowly heated to 130° C and finally kept at this temperature for 2.5 hours. Then, the dimethylsulfoxide was distilled off in vacuo, andthe residue was stirred into a solution of 40 gm of sodium acetate in 400 ml of water, filtered off and washed with water and ice-cold methanol, yielding 90.0 gm (98% of theory) of 3-oxo-naphth[2,1-d]isothiazoline-2-acetic acid methyl ester-1,1-dioxide, m.p. 188° C (methanol/ethylene chloride).

Workup

  1. distillationThe majority of the alcohol was subsequently distilled off
  2. dissolutionthe residual sodium salt of 3-oxo-naphth[2,1-d]isothiazoline-1,1-dioxide was dissolved in 100 ml of absolute dimethylsulfoxide
  3. temperatureslowly heated to 130° C
  4. distillationThen, the dimethylsulfoxide was distilled off in vacuo
  5. stirringandthe residue was stirred into a solution of 40 gm of sodium acetate in 400 ml of water
  6. filtrationfiltered off
  7. washwashed with water and ice-cold methanol

Sources & evidence

ORD record
ord-7a5b3dd5a1b345bc94801eb7b3c2f7a5
Source dataset
uspto-grants-1976_11
Patent number
US03992535

Reaction notes

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