1: 1.) aq. NaIO4, NaOH, 2.) PPTS, 4A molecular sieves / 1.) RT, 10 min, 2.) 90 deg C, 2 h 2: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, hexane, from -78 deg C to RT, 3.5 h View Scheme

1: With periodic acid in tetrahydrofuran 0.333333 h; 2: With sodium cyanoborohydride in acetic acid 1.5 h;