1: 1.) n-BuLi, diisopropylamine / 1.) THF, hexane, - 78 deg C 2.) -78 deg C, 1 h. 2: 67 percent / N-Chloro-succinimide / tetrahydrofuran / 1.) -78 deg C, 3 h 2.) 0 deg C, 30 min. d.e. 96 percent 3: 95 percent / Ca(BH4)2 / tetrahydrofuran 4: NaOMe / methanol / Ambient temperature; e.e. 90percent View Scheme

1: 1.) n-BuLi, diisopropylamine / 1.) THF, hexane, - 78 deg C 2.) -78 deg C, 1 h. 2: 67 percent / N-Chloro-succinimide / tetrahydrofuran / 1.) -78 deg C, 3 h 2.) 0 deg C, 30 min. d.e. 96 percent 3: 95 percent / Ca(BH4)2 / tetrahydrofuran 4: 67 percent / NaOMe / methanol / Ambient temperature; e.e. 90percent View Scheme