1: 1.) n-BuLi / 1.) THF, HMPA, hexane, -78 deg C, 1.5 h, 2.) 6 h 2: 5percent sodium amalgam, disodium hydrogen phosphate / methanol / 2 h / 0 °C View Scheme

1: BuLi, N,N'-dimethyl-N,N'-propyleneurea / hexane; tetrahydrofuran / 1.) -78 deg C, 1 h; 2.) -50 deg C, 1 h 2: KOH / diethyl ether; methanol / 1 h / Ambient temperature 3: Na, dibenzo<18>crown-6 / liquid ammonia; tetrahydrofuran / 0.03 h 4: PBr3 / diethyl ether / 1 h / 0 °C View Scheme

1.1: n-butyl lithium / tetrahydrofuran; hexane / 1.5 h / 0 - 20 °C 1.2: 81 percent / tetrahydrofuran; hexane / 3 h / -20 - 20 °C 2.1: (+)-diisopropyl tartrate; titanium isopropoxide; tert-butyl hydroperoxide / CH2Cl2; decane / -20 °C 3.1: 95 percent / pyridine / CH2Cl2 / 48 h / -10 °C 4.1: perchloric acid / tetrahydrofuran; H2O / 2 h / Heating 4.2: 67 percent / 2,6-lutidine / CH2Cl2 / 1 h / -20 °C 5.1: vanadil acetylacetonate; t-butyl hydroperoxide; pyridinium para-toluenesulfonate / 4 Angstroem molecular sieve / various solvent(s); CH2Cl2; decane / 29 h / 20 °C 6.1: sodium iodide; 18-c-6 / butan-2-one / Heating 6.2: 81 percent / tributyltin hydride; AIBN / toluene / 3 h / Heating 7.1: 93 percent / triethylamine / CH2Cl2 / 3 h / -78 °C 8.1: n-butyl lithium / tetrahydrofuran; hexane / 0.5 h / -78 °C 8.2: tetrahydrofuran; hexane / 0.5 h 9.1: N-methylmorpholine N-oxide / tetrapropylammonium perruthenate / CH2Cl2 / 2 h / 20 °C 10.1: 673 mg / samarium diiodide / ethanol; tetrahydrofuran / 0.5 h / -78 °C 11.1: 86 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / H2O; CH2Cl2 / 1 h / 0 °C 12.1: 90 percent / samarium diiodide / tetrahydrofuran / 0.5 h / 0 °C 13.1: 4-dimethylaminopyridine / CH2Cl2 14.1: HCl / tetrahydrofuran / 5 h / 0 °C 15.1: 264 mg / sodium hydride / tetrahydrofuran / 0.33 h / 50 °C 16.1: 96 percent / Pd(OH)2 / ethanol; cyclohexane / 12 h / Heating 17.1: 91 percent / N-methylmorpholine N-oxide / tetrapropylammonium perruthenate / CH2Cl2 / 0.5 h / 20 °C 18.1: potassium hexamethyldisilazide / tetrahydrofuran; toluene / 0.5 h 18.2: 85 percent / tetrahydrofuran; toluene / -78 - 20 °C 19.1: 97 percent / 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / H2O; CH2Cl2 / 2 h / 0 °C 20.1: DMSO; oxalyl chloride; Et3N / CH2Cl2 / 0.92 h / -78 °C 21.1: dibutylboron triflate; diisopropylethylamine / CH2Cl2 / 0.5 h / -78 °C 21.2: CH2Cl2 / 3 h / -78 - 20 °C 22.1: 12 mg / pyridine; chromium trioxide / CH2Cl2 / 0.33 h / 20 °C 23.1: 85 percent / HF / H2O; acetonitrile / 3 h / 20 °C 24.1: LiOH / H2O; 1,2-dimethoxy-ethane / 7 h / 80 °C View Scheme

1: BuLi, N,N'-dimethyl-N,N'-propyleneurea / hexane; tetrahydrofuran / 1.) -78 deg C, 1 h; 2.) -50 deg C, 1 h 2: KOH / diethyl ether; methanol / 1 h / Ambient temperature 3: Na, dibenzo<18>crown-6 / liquid ammonia; tetrahydrofuran / 0.03 h View Scheme

1: 1.) n-BuLi / 1.) THF, HMPA, hexane, -78 deg C, 1.5 h, 2.) 6 h 2: 5percent sodium amalgam, disodium hydrogen phosphate / methanol / 2 h / 0 °C 3: 91 percent / PBr3, pyridine / diethyl ether / 6 h / -5 °C 4: 78 percent / dimethylformamide / 24 h / Ambient temperature 5: 1.) n-BuLi, 3.) H2O, KOH 6: 63 percent / Li, ethylamine / diethyl ether / 1 h / -78 °C 7: 1.) PBr3, pyridine / 1.) ether, 2.) DMF, ambient temperature 8: 1.) n-BuLi, 3.) H2O, KOH 9: 70 percent / Li, ethylamine / diethyl ether 10: 1.) n-BuLi / 1.) THF, HMPA, 2.) -78 deg C 11: 50 percent / Li, ethylamine / diethyl ether / -78 °C View Scheme

carbon tetrabromide; triphenylphosphine in benzene T=0°C; 2 h;

pyridine; phosphorus tribromide in diethyl ether T=0°C; 3 h; Darkness;

1.1: selenium oxide; tert-butyl hydroperoxide; silica gel / CH2Cl2 / 24 h 1.2: 60 percent / sodium borohydride / ethanol / 0 °C 2.1: triethylamine / CH2Cl2 / -40 °C 3.1: 9.4 g / lithium bromide / tetrahydrofuran; CH2Cl2 / -20 °C View Scheme

1: 72 percent / NaBH4 / methanol / 5 h / -10 °C 2: 94 percent / PBr3, pyridine / diethyl ether / 6 h / 0 °C View Scheme

1: selenium(IV) oxide; 3-chloro-2-hydroxybenzoic acid; tert.-butylhydroperoxide / dichloromethane; water / 30 h / 20 °C 2: pyridine; phosphorus tribromide / diethyl ether / 3 h / 0 °C / |Darkness View Scheme