1.1: 91 percent / LiAlH4 / diethyl ether / -78 °C 2.1: 93 percent / Et2Zn / diethyl ether / 20 °C 3.1: N-iodosuccinimide / 20 °C 4.1: n-Bu3SnH; AIBN / benzene / Heating 5.1: 97 percent / imidazole / dimethylformamide / 20 °C 6.1: 78 percent / TiCl4 / CH2Cl2 / -78 - -40 °C 7.1: 98 percent / 2,6-lutidine / CH2Cl2 / 0 °C 8.1: 89 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / CH2Cl2; H2O / 20 °C 9.1: (COCl)2; DMSO / CH2Cl2 / -78 °C 9.2: 90 percent / Et3N / CH2Cl2 / -78 - 0 °C 10.1: 2.83 g / tetrahydrofuran / 2 h / 0 - 20 °C 11.1: 99 percent / pTSA*H2O / dioxane; H2O / 2 h / 50 °C 12.1: 76 percent / tetrahydrofuran / 1 h / 0 - 20 °C 13.1: 92 percent / [bis(trifluoroacetoxy)iodobenzene] / tetrahydrofuran / 0.25 h / 20 °C 14.1: 9-borabicyclo[3.3.1]nonane / tetrahydrofuran / 4 h / 20 °C 14.2: 75 percent / Cs2CO3; Ph3As; H2O / PdCl2(1,1'-bis(diphenylphosphino)ferrocene)2 / dimethylformamide; tetrahydrofuran / 2 h / 20 °C 15.1: 85 percent / pTSA*H2O / dioxane; H2O / 3 h / 55 °C 16.1: potassium bis(trimethylsilyl)amide / tetrahydrofuran; toluene / 0.5 h / -78 °C 17.1: 99 percent / hydrogen fluoride-pyridine; pyridine / tetrahydrofuran / 2 h / 20 °C 18.1: 93 percent / 2,6-lutidine / CH2Cl2 / 0.5 h / -30 °C 19.1: 84 percent / Dess-Martin periodinane / CH2Cl2 / 1.5 h / 25 °C 20.1: 99 percent / HF*pyridine / tetrahydrofuran / 2 h / 25 °C 21.1: 49 percent / 3,3-dimethyldioxirane / CH2Cl2; acetone / 2 h / -50 - -30 °C View Scheme

1.1: 91 percent / LiAlH4 / diethyl ether / -78 °C 2.1: 93 percent / Et2Zn / diethyl ether / 20 °C 3.1: N-iodosuccinimide / 20 °C 4.1: n-Bu3SnH; AIBN / benzene / Heating 5.1: 97 percent / imidazole / dimethylformamide / 20 °C 6.1: 78 percent / TiCl4 / CH2Cl2 / -78 - -40 °C 7.1: 98 percent / 2,6-lutidine / CH2Cl2 / 0 °C 8.1: 89 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / CH2Cl2; H2O / 20 °C 9.1: (COCl)2; DMSO / CH2Cl2 / -78 °C 9.2: 90 percent / Et3N / CH2Cl2 / -78 - 0 °C 10.1: 2.83 g / tetrahydrofuran / 2 h / 0 - 20 °C 11.1: 99 percent / pTSA*H2O / dioxane; H2O / 2 h / 50 °C 12.1: 76 percent / tetrahydrofuran / 1 h / 0 - 20 °C 13.1: 92 percent / [bis(trifluoroacetoxy)iodobenzene] / tetrahydrofuran / 0.25 h / 20 °C 14.1: 9-borabicyclo[3.3.1]nonane / tetrahydrofuran / 5 h / 20 °C 14.2: 77 percent / Cs2CO3; Ph3As; H2O / PdCl2(1,1'-bis(diphenylphosphino)ferrocene)2 / dimethylformamide; tetrahydrofuran / 3 h / 20 °C 15.1: 71 percent / pTSA*H2O / dioxane; H2O / 3 h / 55 °C 16.1: 0.055 g / potassium bis(trimethylsilyl)amide / tetrahydrofuran; toluene / 1 h / -78 °C 17.1: Dess-Martin periodinane / CH2Cl2 / 1 h / 20 °C 18.1: 0.052 g / NaBH4 / methanol; tetrahydrofuran / 1 h / -78 - 20 °C 19.1: 94 percent / hydrogen fluoride-pyridine; pyridine / tetrahydrofuran / 2 h / 20 °C 20.1: 92 percent / HF*pyridine / tetrahydrofuran / 2 h / 0 - 20 °C 21.1: 97 percent / 3,3-dimethyldioxirane / CH2Cl2; acetone / 2.5 h / -78 - -50 °C View Scheme

1.1: 91 percent / LiAlH4 / diethyl ether / -78 °C 2.1: 93 percent / Et2Zn / diethyl ether / 20 °C 3.1: N-iodosuccinimide / 20 °C 4.1: n-Bu3SnH; AIBN / benzene / Heating 5.1: 97 percent / imidazole / dimethylformamide / 20 °C 6.1: 78 percent / TiCl4 / CH2Cl2 / -78 - -40 °C 7.1: 98 percent / 2,6-lutidine / CH2Cl2 / 0 °C 8.1: 89 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / CH2Cl2; H2O / 20 °C 9.1: (COCl)2; DMSO / CH2Cl2 / -78 °C 9.2: 90 percent / Et3N / CH2Cl2 / -78 - 0 °C 10.1: 2.83 g / tetrahydrofuran / 2 h / 0 - 20 °C 11.1: 99 percent / pTSA*H2O / dioxane; H2O / 2 h / 50 °C 12.1: 76 percent / tetrahydrofuran / 1 h / 0 - 20 °C 13.1: 92 percent / [bis(trifluoroacetoxy)iodobenzene] / tetrahydrofuran / 0.25 h / 20 °C 14.1: 9-borabicyclo[3.3.1]nonane / tetrahydrofuran / 5 h / 20 °C 14.2: 77 percent / Cs2CO3; Ph3As; H2O / PdCl2(1,1'-bis(diphenylphosphino)ferrocene)2 / dimethylformamide; tetrahydrofuran / 3 h / 20 °C 15.1: 71 percent / pTSA*H2O / dioxane; H2O / 3 h / 55 °C 16.1: 0.055 g / potassium bis(trimethylsilyl)amide / tetrahydrofuran; toluene / 1 h / -78 °C 17.1: Dess-Martin periodinane / CH2Cl2 / 1 h / 20 °C 18.1: 0.052 g / NaBH4 / methanol; tetrahydrofuran / 1 h / -78 - 20 °C 19.1: 94 percent / hydrogen fluoride-pyridine; pyridine / tetrahydrofuran / 2 h / 20 °C 20.1: 92 percent / HF*pyridine / tetrahydrofuran / 2 h / 0 - 20 °C View Scheme

1.1: 91 percent / LiAlH4 / diethyl ether / -78 °C 2.1: 93 percent / Et2Zn / diethyl ether / 20 °C 3.1: N-iodosuccinimide / 20 °C 4.1: n-Bu3SnH; AIBN / benzene / Heating 5.1: 97 percent / imidazole / dimethylformamide / 20 °C 6.1: 78 percent / TiCl4 / CH2Cl2 / -78 - -40 °C 7.1: 98 percent / 2,6-lutidine / CH2Cl2 / 0 °C 8.1: 89 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / CH2Cl2; H2O / 20 °C 9.1: (COCl)2; DMSO / CH2Cl2 / -78 °C 9.2: 90 percent / Et3N / CH2Cl2 / -78 - 0 °C 10.1: 2.83 g / tetrahydrofuran / 2 h / 0 - 20 °C 11.1: 99 percent / pTSA*H2O / dioxane; H2O / 2 h / 50 °C 12.1: 76 percent / tetrahydrofuran / 1 h / 0 - 20 °C 13.1: 92 percent / [bis(trifluoroacetoxy)iodobenzene] / tetrahydrofuran / 0.25 h / 20 °C 14.1: 9-borabicyclo[3.3.1]nonane / tetrahydrofuran / 4 h / 20 °C 14.2: 75 percent / Cs2CO3; Ph3As; H2O / PdCl2(1,1'-bis(diphenylphosphino)ferrocene)2 / dimethylformamide; tetrahydrofuran / 2 h / 20 °C 15.1: 85 percent / pTSA*H2O / dioxane; H2O / 3 h / 55 °C 16.1: potassium bis(trimethylsilyl)amide / tetrahydrofuran; toluene / 0.5 h / -78 °C 17.1: 99 percent / hydrogen fluoride-pyridine; pyridine / tetrahydrofuran / 2 h / 20 °C 18.1: 93 percent / 2,6-lutidine / CH2Cl2 / 0.5 h / -30 °C 19.1: 84 percent / Dess-Martin periodinane / CH2Cl2 / 1.5 h / 25 °C 20.1: 99 percent / HF*pyridine / tetrahydrofuran / 2 h / 25 °C View Scheme