Thiophosgene → 6-fluoro-5-isothiocyanato-3-(5-methyl-1,2,4-oxadiazol-3-ylmethyl)-2(3H)-benzothiazolone

HRID 1199622Notes

Reaction equation

HRID 1199622 reaction equation
[NH2:1][C:2]1[C:3]([F:19])=[CH:4][C:5]2[S:9][C:8](=[O:10])[N:7]([CH2:11][C:12]3[N:16]=[C:15]([CH3:17])[O:14][N:13]=3)[C:6]=2[CH:18]=1.[C:20](Cl)(Cl)=[S:21].C(=O)(O)[O-].[Na+]>ClCCl>[F:19][C:3]1[C:2]([N:1]=[C:20]=[S:21])=[CH:18][C:6]2[N:7]([CH2:11][C:12]3[N:16]=[C:15]([CH3:17])[O:14][N:13]=3)[C:8](=[O:10])[S:9][C:5]=2[CH:4]=1

Participants

5

Reactant 3

HCID 10040ThiophosgeneHCID 516892Sodium Bicarbonate2×HCID 199794815-amino-6-fluoro-3-(5-methyl-1,2,4-oxadiazol-3-ylmethyl)-2(3H)-benzothiazolone

Product 1

HCID 199794866-fluoro-5-isothiocyanato-3-(5-methyl-1,2,4-oxadiazol-3-ylmethyl)-2(3H)-benzothiazoloneYield 97.4%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A mixture of 5-amino-6-fluoro-3-(5-methyl-1,2,4-oxadiazol-3-ylmethyl)-2(3H)-benzothiazolone (1.33 g), dichloromethane (10 ml) and ice (10 g) was prepared. To this mixture was added thiophosgene (0.7 g), and then portionwise added sodium bicarbonate at a temperature of 5° to 10° C. so as to make the mixture slightly alkaline. The mixture was stirred for 20 minutes, and tested to confirm whether the mixture was alkaline (if the mixture was acidic, then a further amount of sodium bicarbonate was added). The dichloromethane layer was separated, and the aqueous layer was extracted with fresh dichloromethane (10 ml×2). The dichloromethane layers were gathered together, washed with water, and distilled to remove the dichloromethane solvent therefrom. The resulting solid residue was recrystallized from a toluene-hexane solvent mixture, so that the aimed compound, i.e. 6-fluoro-5-isothiocyanato-3-(5-methyl-1,2,4-oxadiazol-3-ylmethyl)-2(3H)-benzothiazolone (1.49 g) was obtained. m.p. 168°-170° C.

Workup

  1. customwas prepared
  2. customat a temperature of 5° to 10° C.
  3. customThe dichloromethane layer was separated
  4. extractionthe aqueous layer was extracted with fresh dichloromethane (10 ml×2)
  5. washwashed with water
  6. distillationdistilled
  7. customto remove the dichloromethane solvent
  8. customThe resulting solid residue was recrystallized from a toluene-hexane solvent mixture, so that the aimed compound

Sources & evidence

ORD record
ord-54b97de91f244af48cdf49f07ca71460
Source dataset
uspto-grants-1990_02
Patent number
US04902335

Reaction notes

Loading…