1: dimsylsodium, toluene-p-sulphonic acid/silica gel / light petroleum 2: 97 percent / toluene-p-sulphonic acid/silica gel / H2O; tetrahydrothiophene 1,1-dioxide; CH2Cl2 3: 850 mg / diethyl ether / 60 h 4: 64 percent / lithium triethylborohydride / tetrahydrofuran / 0.25 h / 20 °C 5: 61 percent / H2 / platinum oxide / 18 h / 150 °C / ethyl palmitate View Scheme

Multi-step reaction with 3 steps 1: dimsylsodium, toluene-p-sulphonic acid/silica gel / light petroleum2: 97 percent / toluene-p-sulphonic acid/silica gel / H2O; tetrahydrothiophene 1,1-dioxide; CH2Cl2 3: 850 mg / diethyl ether / 60 h