5-Bromo-1-benzothiophene → 5-Methoxy-1-benzothiophene

Participants

Reaction Conditions

Reaction Steps

To a solution of 1.8 g of 5-bromobenzo[b]thiophene in 2 mL of anhydrous DMF and 1 mL of MeOH was added 686 mg of NaOMe. The mixture was heated to 110° C. (bath temp), and 121 mg of CuBr was added. The brown suspension was heated at 110° C. for ˜2 h and at ˜145° C. for 30 min. The reaction was quenched with ca. 50 mL of H2O and the mixture was extracted with 100 mL of Et2O (2×), EtOAc (1×), and CH2Cl2 (1×). The organic layers were washed with 50 mL of brine, combined, dried over MgSO4, concentrated, and flash chromatographed with 3% Et2O-hexanes to afford 894.5 mg (64%) of the title compound along with 168.8 mg (9.4%) of 5-bromobenzo[b]-thiophene.

Provenance & Evidence