1.1: LDA; chlorotrimethylsilane / hexane; tetrahydrofuran / 1 h / -78 °C 1.2: NBS / tetrahydrofuran; hexane / 1 h / 0 °C 2.1: 797 mg / p-TsOH*H2O / ethanol / 2 h / 0 °C 3.1: 83 percent / PCC; sodium acetate; 4 Angstroem MS / CH2Cl2 / 1 h / 20 °C 4.1: 63 percent / Et2Zn / RhCl(PPh3)3 / tetrahydrofuran; hexane / 0.08 h / 0 °C View Scheme

1.1: LDA; chlorotrimethylsilane / hexane; tetrahydrofuran / 1 h / -78 °C 1.2: NBS / tetrahydrofuran; hexane / 1 h / 0 °C 2.1: 797 mg / p-TsOH*H2O / ethanol / 2 h / 0 °C 3.1: 83 percent / PCC; sodium acetate; 4 Angstroem MS / CH2Cl2 / 1 h / 20 °C 4.1: 63 percent / Et2Zn / RhCl(PPh3)3 / tetrahydrofuran; hexane / 0.08 h / 0 °C View Scheme