1,2-Diiodoethane → 3-Diethylamino-7-iodopyrazolo[1,5-a]pyridine

Beteiligte Stoffe

Reaktionsschritte

A solution of 3-diethylaminopyrazolo[1,5-a]pyridine (0.57 g, 3.00 mmol) in THF (5.00 mL) was cooled to −78° C. and treated with a solution of n-butyl lithium (1.20 M in hexanes, 3.25 mL, 3.90 mmol). The reaction was stirred for 30 minutes then treated with a solution of 1,2-diiodoethane (1.01 g, 3.60 mmol) in THF (10 mL). The reaction was stirred at −78° C. for 3 hours then quenched with saturated NaHCO3 at −78° C. and warmed to room temperature. The reaction was diluted with water and extracted twice with methylene chloride, dried over MgSO4 and concentrated in vacuo to give a dark green oil which was subjected to column chromatography (5% ethyl acetate/hexane) to give 0.59 g (63%) of a yellow oil as the title compound: 1H NMR (400 MHz, CDCl3) δ 7.92 (s, 1H), 7.58 (dd, J=8.8, 1.2 Hz, 1H), 7.31 (d, J=8.0 Hz, 1H), 6.81–6.76 (m, 1H), 3.13 (q, J=7.1 Hz, 4H), 1.06 (t, J=7.1 Hz, 6H); MS (EI) m/z 316.14 (M++H).

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