Chloroacetic Acid → HCID 70363008, compound

HRID 1383132Notes

Reaction equation

HRID 1383132 reaction equation
NC1[S:3][C:4]2[CH:10]=[CH:9][CH:8]=[CH:7][C:5]=2N=1.[OH-].[Na+].Cl[CH2:14][C:15]([OH:17])=O.[Na].[NH2:19]C1C=CC=CC=1C(S)C(O)=O.Cl>O.C(O)CO>[O:17]=[C:15]1[CH2:14][CH:5]2[CH2:7][CH:8]=[CH:9][CH:10]=[C:4]2[S:3][NH:19]1

Participants

9

Reactant 6

HCID 300Chloroacetic AcidHCID 313Hydrochloric AcidHCID 8706Benzo(d)thiazol-2-amineHCID 14798Sodium HydroxideHCID 5360545SodiumHCID 22914686HCID 22914686, compound2×

Product 1

HCID 70363008HCID 70363008, compound

Reagents, catalysts & solvents 2

HCID 174Ethylene GlycolSolventHCID 962WaterSolvent

Conditions

Temperature
45 °C

Procedure

A mixture f 150 parts of 2-aminobenzothiazole, 150 parts of solid sodium hydroxide and 300 parts of ethylene glycol is stirred for 6 hours at 130°-140° C. (Example 1 of European Pat. No. 0,039,483). The mixture is cooled to 45° C., 113 parts of chloroacetic acid are added so that the internal temperature does not exceed 50° C., and stirring is then continued for 2 hours at this temperature. The mixture is then heated to 80°-90° C. and kept at this temperature for 1 hour, and the resulting suspension of the sodium salt of 2-aminophenyl thioglycolic acid of the formula (11) is then allowed to run into a mixture of 2500 parts of water and 550 parts of 30% strength hydrochloric acid, the temperature increasing to 60° C. During this procedure, the 2-aminophenyl thioglycolic acid liberated undergoes rapid cyclization to give 3-oxo-dihydrobenzothiazine of the formula (12), which is the stable anhydride of the unstable free acid: ##STR22## Stirring is continued for 30 minutes at 60° to 70° C., the mixture is cooled to room temperature and the precipitated product is filtered off, washed neutral with water and dried at 120° C. in a through-circulation oven. 150 parts of 3-oxo-dihydrobenzothiazine of melting point 175° C. are obtained; this corresponds to a yield of 90.0% of theory, based on 2-aminobenzothiazole employed.

Workup

  1. customdoes not exceed 50° C.
  2. temperatureThe mixture is then heated to 80°-90° C.
  3. waitkept at this temperature for 1 hour
  4. temperaturethe temperature increasing to 60° C

Sources & evidence

ORD record
ord-d135ea2a6dc044e8b94a42523037999e
Source dataset
uspto-grants-1989_02
Patent number
US04808752

Reaction notes

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