lithium hydroxide in tetrahydrofuran; water 1.5 h;

1: 1.) HMPA, 2.) iodine-silver trifluoracetate / 1.) THF, 2.) CH2Cl2, -78 deg C 3: 1.)disiamylborane, 2.) HOAc / 1.) THF, -40 deg C, 2 h , - 20 deg C, 4 h, 0 deg C, 1 h, 2.) 25 deg C, 4 h 4: 1.) t-BuLi, 2.) CuI*Me2s / ether/THF 5: 100 percent / LiOH / tetrahydrofuran; H2O / 14 h / 25 °C View Scheme

2: 1.)disiamylborane, 2.) HOAc / 1.) THF, -40 deg C, 2 h , - 20 deg C, 4 h, 0 deg C, 1 h, 2.) 25 deg C, 4 h 3: 1.) t-BuLi, 2.) CuI*Me2s / ether/THF 4: 100 percent / LiOH / tetrahydrofuran; H2O / 14 h / 25 °C View Scheme

1: 1.)disiamylborane, 2.) HOAc / 1.) THF, -40 deg C, 2 h , - 20 deg C, 4 h, 0 deg C, 1 h, 2.) 25 deg C, 4 h 2: 1.) t-BuLi, 2.) CuI*Me2s / ether/THF 3: 100 percent / LiOH / tetrahydrofuran; H2O / 14 h / 25 °C View Scheme

1: 1.) t-BuLi, 2.) CuI*Me2s / ether/THF 2: 100 percent / LiOH / tetrahydrofuran; H2O / 14 h / 25 °C View Scheme

2: 100 percent / LiOH / tetrahydrofuran; H2O / 1.5 h View Scheme