반응 #70267

반응 방정식

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

수율 17.5%

용매

dioxane water

반응 조건

후처리

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

실험 절차

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.

출처