Tetrahydrofuran → Methoxyindoline

Participants

Reaction Steps

To an ice-cold solution of indoline 9 (377 mg, 1.6 mmol) dissolved in tetrahydrofuran (5 mL) and kept under an argon atmosphere was added lithium triethylborohydride (3.2 mL, 3.2 mmol), and the mixture was stirred over the range of 0° C. to room temperature for 20 h. The reaction mixture was quenched with 3N hydrochloric acid, and volatiles were removed under vacuum. The resulting solution was acidified to pH 2 with additional 3N hydrochloric acid and washed with methylene chloride. The aqueous solution was basified with saturated aq. sodium bicarbonate and extracted with methylene chloride. The organic extracts were washed with brine and dried (MgSO4). Removal of solvents gave crude methoxyindoline (200 mg, 65% yield) as a brownish yellow oil, which was used without further purification.

Provenance & Evidence