Lithium diisopropylamide → tert-butyl 4-((6-cyanobenzofuran-2-yl)(hydroxy)methyl)-5-methoxy-7-methyl-1H-indole-1-carboxylate

Participants

Reaction Steps

To a solution of benzofuran-6-carbonitrile (CAS #: 17450-68-9) (29.7 mg, 0.207 mmol) in THF (1.7 mL), 1.8M LDA (heptane/THF/ethylbenzene, 0.125 mL, 0.225 mmol) was added at −78° C. After stirring for 30 min., a solution of tert-butyl 4-formyl-5-methoxy-7-methyl-1H-indole-1-carboxylate (Example 19-D) (50 mg, 0.173 mmol) in THF (1.0 mL) was added to the reaction mixture at the same temperature. After stirring for 5 minutes the reaction mixture was diluted with MeOH (1 mL), sat. aq. NH4Cl (5 mL), brine (5 mL) and EtOAc (10 mL). The layers were separated and the aqueous layer was extracted with EtOAc. The organic layer was dried over MgSO4, filtered, and concentrated. The resulting residue was purified by flash column chromatography to provide the title compound. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.07 (s, 1H) 7.68-7.80 (m, 1H) 7.60 (dd, J=8.08, 1.52 Hz, 1H) 7.52 (d, J=3.79 Hz, 1H) 6.91 (s, 1H) 6.72-6.86 (m, 2H) 6.49 (dd, J=4.80, 1.01 Hz, 1H) 6.32 (d, J=5.05 Hz, 1H) 3.85 (s, 3H) 2.53 (s, 3H) 1.51-1.61 (m, 9H).

Provenance & Evidence