Sodium Carbonate → 6-Methoxy-2-[4-(2-(1-pyrrolidinyl)ethoxy)phenyl]benzo[b]thiophene

Participants

Reaction Conditions

Reaction Steps

To a slurry of 6-methoxybenzo[b]thiophene-2-boronic acid (Example 1, Part A) (6.43 g, 30.9 mmol) in 310 mL of benzene was added 1-(2-(4-bromophenoxy)ethyl)pyrrolidine (5.80 mL, 28.1 mmol). Upon addition the reaction mixture turned to a yellow homogeneous solution. The reaction flask was then covered with aluminum foil to keep out light. To this was added 1.07 g (0.92 mmol) of tetrakis(triphenylphosphine)-palladium(0), followed by 30 mL of 2.0 N sodium carbonate solution. The biphasic mixture was heated at 85° C. for 3 h with vigorous stirring. The mixture was cooled to 0° C. and 175 mL of brine solution was added. The layers were separated and the aqueous layer was extracted with 1.0 L of EtOAc. The combined organic layers were dried over MgSO4 and concentrated under reduced pressure. The residue was purified by PrepLC (53:35:2 THF-hexanes-TEA) to afford 5.42 g (15.3 mmol, 55%) of an off-white solid.

Provenance & Evidence