Tetrahydrofuran → (S)-7-(quinuclidin-3-yl)-8,9-dihydro-[1,4]diazepino[6,7,1-hi]indazol-6(7H)-one

Participants

Reaction Steps

To a suspension of lithium (S)-1-(2-(quinuclidin-3-ylamino)ethyl)-1H-indazole-7-carboxylate (360 mg, 1.1 mmol) from Step G above in THF (50 mL) was added N,N-diisopropylethylamine (1.2 mL, 6.7 mmol) and the mixture was stirred at ambient temperature for 10 min. To the above reaction mixture was added 1-propanephosphonic acid cyclic anhydride (T3P) (3.6 g, 5.6 mmol) and the reaction was stirred for 2.5 h. The reaction was quenched with saturated aqueous sodium bicarbonate (100 mL), extracted with ethyl acetate (3×250 mL), and the combined organic layers were washed with brine, dried (Na2SO4), filtered, and concentrated under reduced pressure. The crude solid was purified by SCX-2 resin to afford (S)-7-(quinuclidin-3-yl)-8,9-dihydro-[1,4]diazepino[6,7,1-hi]indazol-6(7H)-one (207 mg, 63%): 1H NMR (500 MHz, CD3OD) δ 8.17 (dd, J=7.5, 1.0 Hz, 1H), 8.15 (s, 1H), 8.00 (dd, J=8.0, 1.0 Hz, 1H), 7.31 (t, J=8.0 Hz, 1H), 4.80-4.75 (m, 2H), 4.70-3.80 (m 3H), 3.38-3.34 (m, 1H), 3.20-3.05 (m, 2H), 2.96-2.85 (m, 3H), 2.14-2.00 (m, 1H), 1.95-1.65 (m, 4H); MS (ESI+) m/z 297 (M+H).

Provenance & Evidence