1: 83 percent / LiEt3BH 2: 95 percent / TBAF 3: (COCl)2, DMSO, Et3N 4: 75 percent / CrCl2 5: 74 percent / Pd(PPh3)2Cl2, Et2NH, CuI 6: 80 percent / TsNHNH2, NaOAc 7: 80 percent / PPTS / ethanol / 16 h / 75 °C View Scheme