Reaktion #70260

Reaktionsgleichung

2-bromo-5-nitro-3-phenylpyridine

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

K2CO3

→

2-methoxy-5-nitro-3-phenylpyridine

Ausbeute 60.3%

Lösungsmittel

toluene methanol

Reaktionsbedingungen

Aufarbeitung

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

Vorschrift

A mixture of 2-bromo-5-nitro-3-phenylpyridine (0.72 mmol, 0.2 g), 2-cyclopropyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.86 mmol, 0.16 ml), Pd(PPh3)4 (0.04 mmol, 0.05 g), K2CO3 (2 mmol, 0.28 g) in a toluene/methanol 4:1 mixture (10 ml) was heated at 100° C. for 30 minutes in a microwave, 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-methoxy-5-nitro-3-phenylpyridine (0.1 g, yield 55%) of an unexpected product.

Quelle