1: TBAF / tetrahydrofuran / 1.) 0 deg C, 1 h, 2.) room temperature, 3 h 2: 1.) MsCl, Et3N, 2.) LiCl / 1.) CH2Cl2, -40 deg C, 1 h, 2.) THF, 0 deg C, 2 h View Scheme

tetrabutyl ammonium fluoride in tetrahydrofuran 1.) 0 deg C, 1 h, 2.) room temperature, 3 h; Yield given;