methanol; titanium tetrachloride 1.) CH2Cl2, -78 deg C, 1 h and 20 min, 2.) -20 deg C; Yield given. Multistep reaction;

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;