1: 80 percent / p-TsOH*H2O / acetone / 25 h / 20 °C 2: PDC; Celite / dimethylformamide / 52 h / 20 °C 3: 1.11 g / tetrahydrofuran; diethyl ether / 0 °C 4: 97 percent Turnov. / diethyl ether / 20 h / 20 °C 5: 100 percent / p-TsOH*H2O / methanol / 24 h / 60 °C 6: pyridine / 3 h / 20 °C 7: 165 mg / pyridine; 4-(dimethylamino)pyridine / 27 h / 20 °C 8: 99 percent / HF / acetonitrile / 7 h / 20 °C 9: H2CrO4 / acetone / 6 h / 0 - 20 °C 10: aq. NaOH / 10 h / 20 °C 11: 96 percent / bis(2-oxo-3-oxazolidinyl)phosphinic chloride; Et3N / CH2Cl2 / 3 h / 20 °C View Scheme

1.1: 40 percent / isopropylmagnesium bromide / tetrahydrofuran / 11 h / 4 °C 2.1: 4-(dimethylamino)pyridine; pyridine / 2 h / 20 °C 3.1: 3.1 g / triethylamine; 4-(dimethylamino)pyridine / CH2Cl2 / 11 h / 20 °C 4.1: LHMDS / tetrahydrofuran / 0.5 h / -78 °C 5.1: 1.93 g / NaHCO3; H2O2 / tetrahydrofuran; ethyl acetate / 0.5 h / 20 °C 6.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 6.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 7.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 8.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 9.1: NaOH / H2O / 64 h / 4 °C 10.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: 4-(dimethylamino)pyridine; pyridine / 2 h / 20 °C 2.1: 3.1 g / triethylamine; 4-(dimethylamino)pyridine / CH2Cl2 / 11 h / 20 °C 3.1: LHMDS / tetrahydrofuran / 0.5 h / -78 °C 4.1: 1.93 g / NaHCO3; H2O2 / tetrahydrofuran; ethyl acetate / 0.5 h / 20 °C 5.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 5.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 6.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 7.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 8.1: NaOH / H2O / 64 h / 4 °C 9.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: ozone / methanol / 0.5 h / -78 °C 1.2: Me2S / methanol / 5 h / -78 - 20 °C 2.1: NaH2PO4; 2-methyl-2-butene; sodium chlorite / 2-methyl-propan-2-ol / 2 h / 20 °C 3.1: 134 mg / H2SO4 / ethanol / 9 h / 80 °C 4.1: 40 percent / isopropylmagnesium bromide / tetrahydrofuran / 11 h / 4 °C 5.1: 4-(dimethylamino)pyridine; pyridine / 2 h / 20 °C 6.1: 3.1 g / triethylamine; 4-(dimethylamino)pyridine / CH2Cl2 / 11 h / 20 °C 7.1: LHMDS / tetrahydrofuran / 0.5 h / -78 °C 8.1: 1.93 g / NaHCO3; H2O2 / tetrahydrofuran; ethyl acetate / 0.5 h / 20 °C 9.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 9.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 10.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 11.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 12.1: NaOH / H2O / 64 h / 4 °C 13.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 1.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 2.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 3.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 4.1: NaOH / H2O / 64 h / 4 °C 5.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: HCl / H2O / 5 h / 100 °C 2.1: thionyl chloride / 17 h / 80 °C 3.1: 68 percent / NaHCO3 / acetonitrile / 4 h / 70 °C 4.1: ozone / methanol / 0.5 h / -78 °C 4.2: Me2S / methanol / 5 h / -78 - 20 °C 5.1: NaH2PO4; 2-methyl-2-butene; sodium chlorite / 2-methyl-propan-2-ol / 2 h / 20 °C 6.1: 134 mg / H2SO4 / ethanol / 9 h / 80 °C 7.1: 40 percent / isopropylmagnesium bromide / tetrahydrofuran / 11 h / 4 °C 8.1: 4-(dimethylamino)pyridine; pyridine / 2 h / 20 °C 9.1: 3.1 g / triethylamine; 4-(dimethylamino)pyridine / CH2Cl2 / 11 h / 20 °C 10.1: LHMDS / tetrahydrofuran / 0.5 h / -78 °C 11.1: 1.93 g / NaHCO3; H2O2 / tetrahydrofuran; ethyl acetate / 0.5 h / 20 °C 12.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 12.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 13.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 14.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 15.1: NaOH / H2O / 64 h / 4 °C 16.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: LHMDS / tetrahydrofuran / 0.5 h / -78 °C 2.1: 1.93 g / NaHCO3; H2O2 / tetrahydrofuran; ethyl acetate / 0.5 h / 20 °C 3.1: (diethylamino)diphenylsilyllithium; diethyl zinc / tetrahydrofuran; hexane / -78 °C 3.2: 57 percent / m-chloroperoxybenzoic acid; KHF2 / dimethylformamide / 2 h / 20 °C 4.1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 5.1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 6.1: NaOH / H2O / 64 h / 4 °C 7.1: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1: 58 percent / BuLi; HMPA; diisopropylamine / hexane; tetrahydrofuran / 4 h / -78 °C 2: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 3: NaOH / H2O / 64 h / 4 °C 4: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1: 355 mg / trifluoroacetic acid / CH2Cl2 / 3 h / 20 °C 2: NaOH / H2O / 64 h / 4 °C 3: 149 mg / triethylamine; bis(2-oxo-3-oxazolidinyl)phosphinic chloride / CH2Cl2 / 2 h / 20 °C View Scheme

1: H2CrO4 / acetone / 6 h / 0 - 20 °C 2: aq. NaOH / 10 h / 20 °C 3: 96 percent / bis(2-oxo-3-oxazolidinyl)phosphinic chloride; Et3N / CH2Cl2 / 3 h / 20 °C View Scheme