Chloroacetyl chloride → 7-Nitro-2H-benzo[b][1,4]thiazin-3(4H)-one

HRID 424484Notes

Reaction equation

HRID 424484 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][C:3]=1[SH:11].C(=O)(O)[O-].[Na+].Cl[CH2:18][C:19](Cl)=[O:20]>O1CCCC1.O>[N+:8]([C:5]1[CH:6]=[CH:7][C:2]2[NH:1][C:19](=[O:20])[CH2:18][S:11][C:3]=2[CH:4]=1)([O-:10])=[O:9]

Participants

6

Reactant 3

HCID 6577Chloroacetyl chlorideHCID 516892Sodium BicarbonateHCID 109866912-Amino-5-nitrobenzenethiol

Product 1

HCID 3701217-Nitro-2H-benzo[b][1,4]thiazin-3(4H)-oneYield 48%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

To a stirred solution of 2-amino-5-nitrobenzenethiol (1.72 g, 10.11 mmol) in tetrahydrofuran (10 mL) was added sodium bicarbonate (2.80 g, 33.4 mmol) as a solution in water (40.0 mL). To this dark red solution was added 2-chloroacetyl chloride (0.885 mL, 11.12 mmol). The resulting mixture, which turned faint red, was then stirred at room temperature overnight. The mixture was then diluted with water and extracted three time with dichloromethane . The combined organics were dried, filtered, concentrated, and then chromatographed in 10% ethyl acetate in dichloromethane, giving the desired product (1.02 g, 48.0%). 1H NMR (DMSO-d6) δ 11.17 (s, 1H), 8.24 (d, J=2.7 Hz, 1H), 8.07 (dd, J=9.0, 2.7 Hz, 1H), 7.13 (d, J=9.0 Hz, 1H), 3.60 (s, 2H); MS-EI: (m/z, %) 210 (M+, 100), 181 (40), 131 (46).

Workup

  1. extractionextracted three time with dichloromethane
  2. customThe combined organics were dried
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customchromatographed in 10% ethyl acetate in dichloromethane

Sources & evidence

ORD record
ord-26a2316c781a4c8287a6b7575680c7f5
Source dataset
uspto-grants-2012_01
Patent number
US08106043B2

Reaction notes

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