1: 1.) 2-methyl-2-butene, 10 M borane-dimethylsulfide, 2.) acetic acid, 3.) 3N NaOH, 35percent H2O2 / 1.) THF, 20 deg C, 3 h, 2.) THF, 60 deg C, 7 h, 3.) 40 deg C, 3.5 h 2: 1.) TiCl4, 2.) 50percent aq. methanol / 1.) CH2Cl2, -78 deg C, 1 h and 20 min, 2.) -20 deg C View Scheme

With  sodium hydroxide; 2-methyl-but-2-ene; dimethylsulfide borane complex; dihydrogen peroxide; acetic acid  1.) THF, 20 deg C, 3 h, 2.) THF, 60 deg C, 7 h, 3.) 40 deg C, 3.5 h;  Yield given. Multistep reaction;