1: 70 percent / n-BuLi / tetrahydrofuran; dimethylsulfoxide / 16 h / 20 °C 2: 95 percent / pyridinium toluene-p-sulphonate / methanol / 8 h / 60 °C 3: 42 percent / 2-chloro-1-methylpyridinium iodide / acetonitrile / 18 h / 80 °C 4: LDA / tetrahydrofuran / -100 - 20 °C 5: K2CO3, MeOH, H2O / 2 h / 20 °C 6: (COCl2), DMF / diethyl ether / 2 h / 0 - 20 °C 7: diethyl ether / 16 h / 0 - 20 °C 8: Et3N / PhCO2Ag / 16 h / 20 °C 9: 90 percent / 40 percent aq. HF / tetrahydrofuran / 6 h / 20 °C 10: 62 percent / CrO3 in H2SO4 11: Me3SiI, C5H5N / CHCl3 / 5 h / 60 °C 12: KOH, H2O / 16 h / 20 °C View Scheme

Multi-step reaction with 11 steps 1: 70 percent / n-BuLi / tetrahydrofuran; dimethylsulfoxide / 16 h / 20 °C2: 95 percent / pyridinium toluene-p-sulphonate / methanol / 8 h / 60 °C3: 42 percent / 2-chloro-1-methylpyridinium iodide / acetonitrile / 18 h / 80 °C4: LDA / tetrahydrofuran / -100 - 20 °C5: K2CO3, MeOH, H2O / 2 h / 20 °C6: (COCl2), DMF / diethyl ether / 2 h / 0 - 20 °C7: diethyl ether / 16 h / 0 - 20 °C8: Et3N / PhCO2Ag / 16 h / 20 °C9: 90 percent / 40 percent aq. HF / tetrahydrofuran / 6 h / 20 °C10: 62 percent / CrO3 in H2SO4 11: Me3SiI, C5H5N / CHCl3 / 5 h / 60 °C  

With  2,4,6-trimethyl-pyridine; methanesulfonyl chloride; lithium chloride in  N,N-dimethyl-formamide T=0°C; 2 h;   

Multi-step reaction with 10 steps 1: 70 percent / n-BuLi / tetrahydrofuran; dimethylsulfoxide / 16 h / 20 °C2: 95 percent / pyridinium toluene-p-sulphonate / methanol / 8 h / 60 °C3: 42 percent / 2-chloro-1-methylpyridinium iodide / acetonitrile / 18 h / 80 °C4: LDA / tetrahydrofuran / -100 - 20 °C5: K2CO3, MeOH, H2O / 2 h / 20 °C6: (COCl2), DMF / diethyl ether / 2 h / 0 - 20 °C7: diethyl ether / 16 h / 0 - 20 °C8: Et3N / PhCO2Ag / 16 h / 20 °C9: 90 percent / 40 percent aq. HF / tetrahydrofuran / 6 h / 20 °C10: 62 percent / CrO3 in H2SO4