Pentane → 6-Phenylsulfonyl-1-triisopropylsilanyl-1H-indole

Participants

Reaction Conditions

Reaction Steps

To as stirred solution of 6-bromo-1-triisopropylsilanyl-1H-indole (0.687 g, 1.95 mmol) in THF (12 mL) at −78° C. under nitrogen was added, dropwise over 0.3 h, a solution of tert-butyllithium in pentane (1.7 M, 2.52 mL, 4.29 mmol) (internal temperature was kept below −70° C.). The mixture was stirred at −78° C. for 0.1 h then phenylsulfonyl fluoride (0.26 mL, 0.343 g, 2.15 mmol) was added dropwise. The mixture was stirred at −78° C. then warmed to 20° C. and stirred thus for 1 h. Excess tert-butyllithium was quenched by addition of ice and the resulting mixture was partitioned between water (100 mL) and EtOAc (3×50 mL). The combined organic extracts were dried (Na2SO4) and evaporated in vacuo to give semi-solid. Chromatography (SiO2; gradient elution with 0-40% Et2O in petrol) gave the title compound (0.365 g, 45%). 1H NMR (CDCl3): 8.21 (1H, s), 8.00-7.89 (2H, m), 7.70 (1H, d), 7.63 (1H, dd), 7.57-7.41 (4H, m), 6.69 (1H, d), 1.82-1.65 (3H, m), 1.16 (18H, d).

Provenance & Evidence