1: 85 percent / HCOOH, Et3N, Pd(dba)2*CHCl3, n-Bu3P / tetrahydrofuran / 75 °C 2: 15 percent / CuBr, t-BuOOCOPh / acetonitrile / -23 °C 3: 92 percent / OsO4, pyridine / tetrahydrofuran / Ambient temperature 4: 77 percent Turnov. / DBU, pyridine / toluene / 50 °C 5: 91 percent / pyridine, DMAP / Ambient temperature 6: 94 percent / tetrahydrofuran / -78 °C 7: 81 percent / TBAF / tetrahydrofuran / Ambient temperature View Scheme

1: 85 percent / HCOOH, Et3N, Pd(dba)2*CHCl3, n-Bu3P / tetrahydrofuran / 75 °C 2: 15 percent / CuBr, t-BuOOCOPh / acetonitrile / -23 °C 3: 92 percent / OsO4, pyridine / tetrahydrofuran / Ambient temperature 4: 77 percent Turnov. / DBU, pyridine / toluene / 50 °C 5: 91 percent / pyridine, DMAP / Ambient temperature 6: 94 percent / tetrahydrofuran / -78 °C View Scheme