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

HRID 1917142Notes

Reaction equation

HRID 1917142 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-f2d4425d8814418fb2e76220832266f3
Source dataset
uspto-grants-2013_12
Patent number
US08618286B2

Reaction notes

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