Substrate scope of benzofulvenes^a.

^aAll reactions were carried out with 0.4 mmol 1 and 0.2 mmol 2, 0.01 mmol Cu/L6 and 0.2 mmol of Cs₂CO₃ in 2 mL of Et₂O for 16 h, Cu(i) = Cu(CH₃CN)₄BF₄. Isolated yield. The dr value was determined by the crude ¹H NMR, and the ee value was determined by HPLC analysis.

^bThe reaction was run at 0 °C.

^c R = 1 − N_aph.

^dThe reaction was run at 20 °C.