Potassium Carbonate → 2-Chloro-3-fluoro-5-vinylpyridine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 101 (5.00 g, 23.8 mmol) and 4,4,6-trimethyl-2-vinyl-1,3,2-dioxaborinane (111, 3.29 g, 21.39 mmol, Sigma-Aldrich) in a mixture of TBAF (30.0 mL) and THF (64.0 mL) under an argon atmosphere was added bis(triphenylphosphine)dichloropalladium(II) catalyst (Pd(PPh3)2Cl2, 1.33 g, 1.90 mmol, Sigma-Aldrich) and K2CO3 (8.20 g, 59.4 mmol). The resulting reaction mixture was heated to 60° C. and held for 16 hrs in a sealed bottle. The mixture was cooled to a temperature of about 25° C., diluted with water, and extracted with EtOAc. The organic layer was separated, washed with brine, and concentrated. The residue was chromatographed on a silica gel column eluted with EtOAc:hexanes to provide 3.2 g of 112 as a colorless oil (85% yield). 1H NMR (CDCl3) δ: 5.48 (1H, d, J=10.97 Hz), 5.83 (1H, d, J=17.62 Hz), 6.68 (1H, dd, J=10.97, 17.62 Hz), 7.52 (1H, d, J=1.60 Hz), 8.20 (1H, d, J=1.60 Hz). LC/MS (M+1): m/z=158.

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