hydrogen fluoride

1: conc. H2SO4 / benzene / 3 h / Heating 2: 1.) diisobutylaluminum hydride, 2.) conc. HCl / 1.) toluene, hexane, -78 deg C, 1.5 h, 2.) THF, -78 deg C, 5 min 3: 1.) n-BuLi/N-isopropylcyclohexylamine / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, -78 deg C, 2 h 4: bromine, triphenyl phosphite / benzene / 1 h / Ambient temperature 5: sodium borohydride, tri-n-butyltin chloride / ethanol / 1.) room temp., 30 min, 2.) reflux, 45 min 6: KOH / ethanol / 1 h / Heating 7: 84 percent / HF (g) View Scheme

1: KOH / ethanol / 1 h / Heating 2: 84 percent / HF (g) View Scheme

1: 1.) n-BuLi/N-isopropylcyclohexylamine / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, -78 deg C, 2 h 2: bromine, triphenyl phosphite / benzene / 1 h / Ambient temperature 3: sodium borohydride, tri-n-butyltin chloride / ethanol / 1.) room temp., 30 min, 2.) reflux, 45 min 4: KOH / ethanol / 1 h / Heating 5: 84 percent / HF (g) View Scheme

1: bromine, triphenyl phosphite / benzene / 1 h / Ambient temperature 2: sodium borohydride, tri-n-butyltin chloride / ethanol / 1.) room temp., 30 min, 2.) reflux, 45 min 3: KOH / ethanol / 1 h / Heating 4: 84 percent / HF (g) View Scheme

1: sodium borohydride, tri-n-butyltin chloride / ethanol / 1.) room temp., 30 min, 2.) reflux, 45 min 2: KOH / ethanol / 1 h / Heating 3: 84 percent / HF (g) View Scheme

1: 1.) diisobutylaluminum hydride, 2.) conc. HCl / 1.) toluene, hexane, -78 deg C, 1.5 h, 2.) THF, -78 deg C, 5 min 2: 1.) n-BuLi/N-isopropylcyclohexylamine / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, -78 deg C, 2 h 3: bromine, triphenyl phosphite / benzene / 1 h / Ambient temperature 4: sodium borohydride, tri-n-butyltin chloride / ethanol / 1.) room temp., 30 min, 2.) reflux, 45 min 5: KOH / ethanol / 1 h / Heating 6: 84 percent / HF (g) View Scheme

trifluorormethanesulfonic acid CH2Cl2, -78 deg C -> room temp., overnight; Yield given. Multistep reaction;

1: AlCl3 2: (i) aq. N2H4, (ii) KOH, (iii) (heating) 3: HF View Scheme

1: (i) aq. N2H4, (ii) KOH, (iii) (heating) 2: HF View Scheme