Reacción #70267

Ecuación de reacción

DCM

Cs2CO3

2-chloro-5-nitro-3-phenylpyridine

Intermediate 3

2-chloro-5-nitro-3-phenylpyridine

2-cyclopropyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

→

2-cyclopropyl-5-nitro-3-phenylpyridine

Rendimiento 17.5%

Disolventes

dioxane water

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe solvent was evaporated
2. 2
   Extracciónthe crude mixture was extracted between water and ethyl acetate
3. 3
   OtroThe solid residue was purified by chromatography over SiO2 eluting with hexane/ethyl acetate

Procedimiento

In a schlenck tube, a mixture of 2-chloro-5-nitro-3-phenylpyridine (described in Intermediate 3 (step B)) (1.43 mmol, 0.4 g), 2-cyclopropyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.59 mmol, 0.29 ml), PdCl2dppf.DCM (0.14 mmol, 0.12 g), Cs2CO3 (4.3 mmol, 1.4 g) in a dioxane/water 4:1 mixture (6.5 ml) was heated at 100° C. for 16 hours, under argon atmosphere. The solvent was evaporated and the crude mixture was extracted between water and ethyl acetate. The solid residue was purified by chromatography over SiO2 eluting with hexane/ethyl acetate mixtures affording 2-cyclopropyl-5-nitro-3-phenylpyridine (0.06 g, 17% of yield) of the expected product.

Fuente