Dimethylformamide → Methyl 1,2-benzisothiazole-5-carboxylate

HRID 1880429Notes

Reaction equation

HRID 1880429 reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[S:9][N:8]=[CH:7][C:6]=2[CH:10]=1.[C:11]([O-:14])(=[O:13])C.[Na+].[CH3:16]N(C=O)C>CO.Cl[Pd]Cl>[S:9]1[C:5]2[CH:4]=[CH:3][C:2]([C:11]([O:14][CH3:16])=[O:13])=[CH:10][C:6]=2[CH:7]=[N:8]1

Participants

6

Reactant 3

HCID 6228DimethylformamideHCID 517045Sodium AcetateHCID 178424445-Bromo-1,2-benzothiazole

Product 1

HCID 66920624Methyl 1,2-benzisothiazole-5-carboxylateYield 5%

Reagents, catalysts & solvents 2

HCID 24290Palladium ChlorideCatalystHCID 887MethanolSolvent

Procedure

To a solution of 1.51 g of 5-bromobenzo[d]isothiazole and 825.0 mg of 1,1′-cis(diphenylphosphino)ferrocene]dichloropalladium(II) in 35 mL methanol in a small Parr bottle was added sodium acetate (1.74 g) and DMF (543 μL). The mixture was degassed several times with nitrogen, then shaken under an atmosphere of CO (40 psi) at 50 degrees for 18 hours. The solution was filtered and concentrated. The residue was flash chromatographed (0-20% EtOAc/Haptanes gradient) to yield 61.0 mg (5%) of methyl benzo[d]isothiazole-5-carboxylate as a white solid. 1H NMR (400 MHz, CD3OD) δ ppm 3.96 (s, 3 H) 8.17 (d, J=0.98 Hz, 2 H) 8.84 (s, 1 H) 9.08 (s, 1 H); LC-MS @ 194.1 (M+1).

Workup

  1. customThe mixture was degassed several times with nitrogen
  2. filtrationThe solution was filtered
  3. concentrationconcentrated
  4. customchromatographed (0-20% EtOAc/Haptanes gradient)

Sources & evidence

ORD record
ord-43197e0b7fb24e1fb0bf0f0a99e00d3f
Source dataset
uspto-grants-2012_11
Patent number
US08318762B2

Reaction notes

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