1: 95 percent / Pd(OAc)2; polymer-bound triphenylphosphine; Et3N / dimedone / tetrahydrofuran / 6 h / 20 - 50 °C 2: AD-mix-α; MeSO2NH2; H2O / 2-methyl-propan-2-ol / 168000 h / 3 - 6 °C 3: TBAF / tetrahydrofuran / 24 h / 20 °C 4: 291 mg / DMAP / CH2Cl2 / 20 °C 5: 96 percent / Amberlite IRA-401(OH) / methanol / 2 h / 20 °C View Scheme