1,2-Dimethoxyethane → 3-Thiophen-2-yl-pyridine-2-carbaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A stirred solution of 3-bromo-pyridine-2-carbaldehyde (126 mg, 0.675 mmol) and 2-thiopheneboronic acid (91.6 mg, 0.716 mmol) in a mixture of THF (0.75 mL), DME (2.0 mL) and 2M Na2CO3 (0.75 mL) was degassed with Ar for 15 minutes, after which Pd(PPh3)4 (39 mg, 0.034 mmol) was added and the heterogeneous mixture heated to 90° C. for 4 h. The reaction was quenched with brine (15 mL) and diluted with EtOAc (40 mL). The organic layer was separated, washed with brine (2×15 mL), dried (Na2SO4), filtered and concentrated in vacuo. Purification by flash chromatography on silica gel (Hexanes/EtOAc, 80:20) gave 3-thiophen-2-yl-pyridine-2-carbaldehyde (81 mg, 63%) as a yellow oil. 1H NMR (CDCl3) δ 7.13-7.22 (m, 2H), 7.48-7.57 (m, 2H), 7.92 (dd, 1H, J=7.9, 1.9 Hz), 8.82 (dd, 1H, J=6.0, 1.5 Hz), 10.23 (s, 1H).

Herkunft & Nachweise