To a solution of 5-(perylen-3-yl)thiophene-2-carboxylic acid (120 mg, 0.33 mmol) in 150 mL of dry THF, NaBH4 (720 mg, 60 eq.) was added. Subsequently BF3•Et2O (3.13 mL, 80 eq.) in 15 mL of dry THF was added dropwise over 30 min, and the reaction was stirred overnight at room temperature. The reaction was quenched with water, and the THF was partially evaporated. The mixture was extracted with DCM (3×100 mL) washed with water and brine, dried over Na₂SO₄, filtered, and evaporated to dryness. The crude product was purified by column chromatography on silica gel using a toluene/DCM (20/80) as eluent to afford 1 as a yellow solid (98 mg, 85%).