Reaction #8342

Reaction equation

carbon monoxide

sodium acetate

CH2Cl2

6-bromo-4-(2-pyridin-2-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-3-yl)-quinoline

→

4-(2-Pyridin-2-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-3-yl)-quinoline-6-carboxylic acid methyl ester

Solvents

methanol

Conditions

Workup

1. 1
   TemperatureThe mixture is cooled
2. 2
   Filtrationfiltered
3. 3
   Concentrationconcentrated in vacuo
4. 4
   OtherThe product is partitioned between ethyl acetate
5. 5
   DryingThe organic layer is dried over sodium sulfate
6. 6
   Concentrationconcentrated in vacuo
7. 7
   OtherThe residue is chromatographed on SiO2 (dichloromethane to 2% methanol/dichloromethane)
8. 8
   Otherto yield a solid, 918 mg (97%)

Procedure

To a mixture of sodium acetate (0.84 g, 10.2 mmol) and [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium (II):CH2Cl2 (42 mg, 0.05 mmol) in methanol (40 mL) is added 6-bromo-4-(2-pyridin-2-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-3-yl)-quinoline (1.0 g, 2.56 mmol). The mixture is heated at 90° C. under 68 psi carbon monoxide for 24 h. The mixture is cooled, filtered, and concentrated in vacuo. The product is partitioned between ethyl acetate and: water. The organic layer is dried over sodium sulfate and concentrated in vacuo. The residue is chromatographed on SiO2 (dichloromethane to 2% methanol/dichloromethane) to yield a solid, 918 mg (97%).

Source