Bromide ion → 1H-Indazole

Participants

Reaction Conditions

Reaction Steps

A mixture of bromide (IXb-75) (120 mg, 0.24 mmol), N,N-dicyclohexylmethylamine (52 mg, 0.27 mmol), 4-(tributylstannyl)thiazole (138 mg, 0.37 mmol), dihydrogen dichlorobis(di-tert-butylphosphinito-kP)palladate(2-) (7 mg, 0.01 mmol) in DMF (3 mL) was stirred at 135° C. for 19 h. The mixture was then cooled to RT and partitioned between EtOAc (20 mL) and saturated aqueous NaHCO3 solution (10 mL). The aqueous layer was extracted with EtOAc (2×15 mL). The combined organic solutions were dried (MgSO4), filtered and concentrated. The orange residue was purified by LCMS (column LUNA 10μ C18(2) 00G-4253-V0 250×50 mm) using water-acetonitrile (0.1% AcOH) as eluent (in gradient; flow 80 mL/min) to afford azaindole (I-116) (24.1 mg, 26%). 1H NMR (400 MHz, CDCl3) δ 1.51-1.67 (m, 4H), 2.03-2.16 (m, 6H), 2.57-2.64 (m, 1H), 3.04-3.12 (m, 5H), 3.82 (t, J=6.0 Hz, 2H), 3.84-3.87 (m, 2H), 6.44 (d, J=3.4 Hz, 1H), 7.31 (d, J=3.4 Hz, 1H), 7.80 (d, J=1.9 Hz, 1H), 8.01 (s, 1H), 8.05 (d, J=1.9 Hz, 1H), 10.29 (br s, 1H).

Provenance & Evidence