1: 1) n-BuLi, 2) HMPA / 1) THF, hexane, -78 deg C to room temperature, 2) THF, hexane, -78 deg C 2: 1) n-BuLi / 1) THF, hexane, -78 deg C to room temperature, 2) THF, hexane, -78 deg C to room temperature 3: TBAF, ethyl acrylate / acetonitrile / 0.83 h View Scheme