Dimethylformamide → 2-tert-Butyl-4-chloro-5-phenylisothiazol-3(2H)-one 1,1-dioxide

HRID 2239531Notes

Reaction equation

[C:1]([Cl:6])(=O)[C:2](Cl)=[O:3].[C:7]([N:11]1C(=O)C(O)=[C:13]([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[S:12]1(=[O:25])=[O:24])([CH3:10])([CH3:9])[CH3:8].CN(C=O)C>C(Cl)Cl>[C:7]([N:11]1[C:2](=[O:3])[C:1]([Cl:6])=[C:13]([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[S:12]1(=[O:25])=[O:24])([CH3:10])([CH3:8])[CH3:9]

Participants

Conditions

Temperature: 50 °C

Procedure

Oxalyl chloride (3.39 g, 2.71 mmol) was added dropwise to a solution of 2-tert-butyl-4-hydroxy-5-phenylisothiazol-3(2H)-one 1,1-dioxide (5 g, 17.77 mol) and DMF (15 mL) in DCM (220 mL) at 0° C. The reaction mixture was heated at 50° C. for 4 h, concentrated and the residue was diluted with EtOAc and washed with water, then brine and evaporated. The residue was purified by silica gel column chromatography, using a 98:2 mixture of petroleum ether and EtOAc as eluant. The product containing fractions were evaporated, the residue was triturated in petroleum ether and the solvent was decanted to give the title compound (3.9 g, 74%) as a solid; 1H NMR (500 MHz, CDCl3): δ 7.97-7.92 (m, 2H), 7.61-7.51 (m, 3H), 1.75 (s, 9H); 13C NMR (125 MHz, CDCl3): δ 156.5, 142.8, 132.3, 129.3, 128.8, 123.4, 63.0, 27.7.

Workup

concentrationconcentrated
additionthe residue was diluted with EtOAc
washwashed with water
custombrine and evaporated
customThe residue was purified by silica gel column chromatography
additiona 98:2 mixture of petroleum ether and EtOAc as eluant
additionThe product containing fractions
customwere evaporated
customthe residue was triturated in petroleum ether
customthe solvent was decanted

Sources & evidence

ORD record: ord-65522911cb97472cbb106dca32b1f82a
Source dataset: uspto-grants-2010_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07723333B2

Reaction notes

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