1.1: 99 percent / imidazole / dimethylformamide / 18 h / 20 °C 2.1: 90 percent / DIBAL-H / CH2Cl2 / 3 h / -78 °C 3.1: 80 percent / CH2Cl2; various solvent(s) / 4.5 h / -78 °C 4.1: 97 percent / Dess-Martin periodinane / CH2Cl2 / 2 h / 20 °C 5.1: 98 percent / diethyl ether / 2 h / -78 - 20 °C 6.1: 99 percent / aq. HF / acetonitrile / 3 h / 20 °C 7.1: BH3*THF / tetrahydrofuran / 2.25 h / -5 °C 7.2: 78 percent / H2O2; NaOH / tetrahydrofuran; methanol; H2O / 0 - 20 °C 8.1: 90 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 - 20 °C 9.1: 80 percent / camphor sulfonic acid / methanol; CH2Cl2 / 2.5 h 10.1: 85 percent / Dess-Martin periodinane / CH2Cl2 / 3 h / 0 °C 11.1: 93 percent / toluene / 7 h / 90 °C 12.1: 86 percent / DIBAL-H / tetrahydrofuran; toluene / 4 h / -78 °C 13.1: 89 percent / oxalyl chloride; DMSO; triethylamine / CH2Cl2 / -78 - -50 °C 14.1: (c-Hex)2BOTf; triethylamine / CH2Cl2 / 2.5 h / -78 °C 14.2: CH2Cl2 / 3 h / -78 °C 14.3: 92 percent / H2O2 / CH2Cl2; methanol; H2O / -78 - 20 °C / pH 7 15.1: LiOH*H2O / tetrahydrofuran; H2O / 7 h / 0 - 20 °C 16.1: 0.217 g / benzene; methanol; hexane / 2 h / 20 °C 17.1: 95 percent / 2,6-lutidine / CH2Cl2 / 0 - 20 °C 18.1: DIBAL-H / CH2Cl2 / 1.75 h / -78 °C 19.1: 0.190 g / KHMDS; 18-crown-6 / tetrahydrofuran; toluene / 4 h / -78 °C 20.1: 91 percent / DIBAL-H / diethyl ether; toluene / 1 h / -78 °C 21.1: 89 percent / Dess-Martin periodinane / CH2Cl2 / 2 h / 0 °C 22.1: 93 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene; lithium chloride / acetonitrile / 2 h / 0 °C 23.1: 82 percent / sodium borohydride; sulfur / tetrahydrofuran / 2 h / 65 °C 24.1: 85 percent / morpholine; tetrakis(triphenylphosphine)palladium(0) / tetrahydrofuran / 24 h 25.1: 78 percent / bis(2-oxo-3-oxazolidinyl)phosphinic chloride; diisopropylethylamine / toluene / 16.5 h / 85 °C 26.1: 90 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 4.5 h / 0 - 20 °C 27.1: 95 percent / aq. HF / acetonitrile / 6 h / 20 °C 28.1: 5 percent / aq. HNO3; acetic acid / 0.02 h / 20 °C View Scheme