1: 18 percent / ZnCl2 / 21 h / 260 °C 2: 1.) BF3*Et2O, 2.) tert-butyl nitrite / 1.) THF, -15 deg C, 2.) THF, 0 deg C, 6 h 3: 12.8 percent / NaBr, aq. HBr, cetyltrimethylammonium bromide <(CTA)Br> / Ambient temperature 4: 1.) Et4NF*xH2O / 1.) DMF, 15 min, 2.) DMF, 100 deg C, 24 h View Scheme

1: 18 percent / ZnCl2 / 21 h / 260 °C 2: 1.) BF3*Et2O, 2.) tert-butyl nitrite / 1.) THF, -15 deg C, 2.) THF, 0 deg C, 6 h 3: 12.8 percent / NaBr, aq. HBr, cetyltrimethylammonium bromide <(CTA)Br> / Ambient temperature 4: 1.) Et4NF*xH2O / 1.) DMF, 15 min, 2.) DMF, 100 deg C, 24 h View Scheme

1: 1.) BF3*Et2O, 2.) tert-butyl nitrite / 1.) THF, -15 deg C, 2.) THF, 0 deg C, 6 h 2: 12.8 percent / NaBr, aq. HBr, cetyltrimethylammonium bromide <(CTA)Br> / Ambient temperature 3: 1.) Et4NF*xH2O / 1.) DMF, 15 min, 2.) DMF, 100 deg C, 24 h View Scheme

tetraethyl ammonium fluoride 1.) DMF, 15 min, 2.) DMF, 100 deg C, 24 h; Yield given. Multistep reaction;

hydrogen bromide; N-hexadecyl-N,N,N-trimethylammonium bromide in water T=40°C; Product distribution;