1: Ti(OiPr)4 / 20 °C 2: H2 / Pd/C / methanol 3: 85 percent / TsOH / 1,2-dimethoxy-ethane / 4 h 4: 85 percent / LHMDS / tetrahydrofuran / -78 °C 5: dicyclohexylcarbodiimide; DMSO; CF3COOH / pyridine 6: 60 percent / TiCl4 / -78 - 35 °C 7: O3; Me2S 8: NaClO2; NaH2PO4 9: HCOONH4 / Pd black 10: NaOH; H2O 11: bis(2-oxo-3-oxazolidinyl)phosphonic chloride View Scheme

1: Ti(OiPr)4 / 20 °C 2: H2 / Pd/C / methanol 3: 85 percent / TsOH / 1,2-dimethoxy-ethane / 4 h 4: 85 percent / LHMDS / tetrahydrofuran / -78 °C 5: dicyclohexylcarbodiimide; DMSO; CF3COOH / pyridine 6: 60 percent / TiCl4 / -78 - 35 °C 7: O3; Me2S 8: NaClO2; NaH2PO4 9: HCOONH4 / Pd black 10: NaOH; H2O View Scheme