1: 100 percent / iodine / CH2Cl2 / -78 °C 2: 64 percent / KH / dimethylformamide / -40 °C 3: p-TsOH*H2O / methanol 4: (COCl)2, dimethyl sulfoxide / CH2Cl2 / -60 °C 5: (TMS)2NK, 18-crown-6*MeCN / tetrahydrofuran / -78 - -40 °C 6: 86 percent / tributyltin hydride, azoisobutyronitrile / benzene / Heating 7: diisobutylaluminium hydride / CH2Cl2 / -78 °C 8: Et3N, 4-dimethylaminopyridine / CH2Cl2 9: 46percent HF / acetonitrile 10: (COCl)2, dimethyl sulfoxide / CH2Cl2 / -60 °C 11: NaClO2, NaHPO4, 2-methylbut-2-ene / butan-1-ol; H2O 12: BF3*Et2O / CH2Cl2 13: diethyl ether 14: 1 M NaOH / methanol 15: H2CrO4 / acetone 16: diethyl ether 17: 63 percent / 40percent aq. NaOH / methanol / Heating View Scheme