2,9-Dimethyl-1,10-phenanthroline → 7-(3,5-difluoro-phenylsulfanyl)-3,4-dihydro-1H-benzo[4,5]furo[2,3-c]pyridine-2-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

Anhydrous DMF was sparged with argon gas for 1 h before being used. 560 μL of a 0.625 M stock solution of 7-iodo-3,4-dihydro-1H-benzo[4,5]furo[2,3-c]pyridine-2-carboxylic acid tert-butyl ester P08 (120 mg, 0.300 mmol) in DMF, 300 μL of a 0.10 M stock solution of neocuproine (6.2 mg, 0.030 mmol) in DMF and 580 μL of a 0.310 M stock solution of copper (I) iodide (34 mg, 0.180 mmol) in DMF were added sequentially into a reaction vial. 3,5-Difluorobenzenethiol (96.5 μL, 0.660 mmol, 2.2 eq) was added neat followed by 630 μL of a 1.0 M stock solution of sodium tert-butoxide (60.5 mg, 0.630 mmol) in DMF. The reaction mixture was shaken at 100° C. for 16 h and the solvent was evaporated. The residue was suspended into DCE:MeOH 95:5 (2.0 mL), passed through a silica gel column (1 g) and eluted with DCE:MeOH 95:5 (3×2.0 mL). The eluent was concentrated to yield crude 7-(3,5-difluoro-phenylsulfanyl)-3,4-dihydro-1H-benzo[4,5]furo[2,3-c]pyridine-2-carboxylic acid tert-butyl ester which was used in the next step without further purification.

Provenance & Evidence