Cesium carbonate → tert-butyl 7-(2-(2-(2-fluoroethoxy)ethoxy)ethoxy)-9H-carbazol-2-ylcarbamate

Participants

Reaction Steps

To tert-butyl 7-hydroxy-9H-carbazol-2-ylcarbamate (165 mg, 0.55 mmol) and 2-(2-(2-fluoroethoxy)ethoxy)ethyl 4-methylbenzenesulfonate (202 mg, 0.66 mmol) in 2 mL of NMP was added Cs2CO3 (179 mg, 0.55 mmol). The mixture was stirred at rt for 15 h under Ar atmosphere and diluted with EtOAc (50 mL). It was washed with water (3×50 mL) and dried over MgSO4. After solvent removal, the residue was chromatographed (hexane/EtOAc) to afford tert-butyl 7-(2-(2-(2-fluoroethoxy)ethoxy)ethoxy)-9H-carbazol-2-ylcarbamate as a white solid (130 mg, 55%). 1H NMR (400 MHz, CDCl3) δ 7.94 (s, 1H), 7.83-7.79 (m, 3H), 6.91 (d, J=2.0 Hz, 1H), 6.86 (dd, J=8.4, 2.0 Hz, 1H), 6.83 (dd, J=8.8, 2.4 Hz, 1H), 6.63 (s, 1H), 4.64 (m, 1H), 4.51 (m, 1H), 4.21 (m, 2H), 3.91 (m, 2H), 3.81-3.71 (m, 6H), 1.55 (s, 9H); MS (ESI) m/z 433 (M+H+).

Provenance & Evidence