反应详情

A mixture of 0.6 g (2.12 mmol) of 2-iodo-4-nitrochlorobenzene (XXI) (G. A. Olah, J. Org. Chem., 1993 (58), 3194-3195), 0.2 g (2.1 mmol) of 2-aminopyrazine (XXII), 2.8 g (8.5 mmol) of cesium carbonate, 0.15 g (0.25 mmol) of Xantphos® (9,9-dimethyl-4,5-bis-(diphenylphosphino)xanthene) and 30 mg (0.13 mmol) of palladium diacetate in 20 ml of dry toluene is heated at 120° C. for 12 hours. After this period of time, the mixture is concentrated under reduced pressure and then taken up in 350 ml of dichloromethane and 200 ml of water. The organic phase is separated, washed with 100 ml of a saturated solution of sodium chloride, dried over magnesium sulphate, and then concentrated under reduced pressure. The resulting product is taken up in 10 ml of dichloromethane, and 0.23 g of the expected product is isolated in the form of a precipitate which is recovered by filtration. The filtrate is purified by silica column chromatography, elution being carried out with a mixture of ethyl acetate and heptane. A further 25 mg of product are thus isolated.

1. waitAfter this period of time
2. concentrationthe mixture is concentrated under reduced pressure
3. customThe organic phase is separated
4. washwashed with 100 ml of a saturated solution of sodium chloride
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated under reduced pressure