Sodium Carbonate → Methyl 3-cyclohexyl-2-phenyl-1H-indole-6-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of methyl 2-bromo-3-cyclohexyl-1H-indole-6-carboxylate (from Step 3) in DME and EtOH (0.2 M, 3:1, v/v) was added phenyl-boronic acid (1.2 eq.) followed by 2 M aqueous Na2CO3 (8.5 eq,). The mixture was degassed with ultrasound for 30 min, then Pd(PPh3)4 (0.1 eq.) was added and mixture degassed with ultrasound for a further 30 min. The reaction was stirred under nitrogen at 90° C. for 6 h and then cooled to RT. Water was added and the solids filtered off. They were washed with Et2O to give the title compound (49%). The combined mother liquors together with the reaction solvents were washed with water (150 ml) and after phase-cut the organic phase was dried over Na2SO4 and evaporated to dryness. The residual solid was crystallized from boiling CHCl3 to give more title compound (38%, 87% total yield). 1H NMR (400 MHz, DMSO-d6, 300 K) δ 1.21-1.48 (m, 3H), 1.65-1.80 (m, 5H), 1.90-2.05 (m, 2H), 2.79-2.95 (m, 1H), 3.88 (s, 3H), 7.2-7.34 (m, 1H), 7.40-7.50 (m, 1H), 7.51-7.60 (m, 3H), 7.60 (d, J 7.6, 1H), 7.84 (d, J 7.6, 1H), 8.00 (s, 1H); MS (ES+) m/z 334 (M+H)+.

Herkunft & Nachweise