The use of PdX2, CuX2 (X= OAc, OCOCF3, or Cl), and catechol together with (S, S)-4, 4′- bisbenzyl-2, 2′-bioxazoline under O2 induces the asymmetric coupling of cinnamyl alcohols and vinyl ethers to give (R)-(+)-2-alkoxy-4-benzylidenetetrahydrofurans in 40− 53 ...