1: 1.) BF3*Et2O, AcOH, Ac2O, 2.) p-TsOH*H2O / 1.) reflux, 18.5 h, 2.) reflux, 20 h 2: 82.2 percent / K2CO3 / acetone; dimethylformamide / 27 h / Heating 3: K2CO3 / acetone; dimethylformamide / 5.5 h / Heating 4: LiOH*H2O / tetrahydrofuran; H2O / 6 h / Ambient temperature View Scheme

1: 96.8 percent / K2CO3 / acetone; dimethylformamide / 5.5 h / Heating 2: 72 percent / LiOH*H2O / tetrahydrofuran; H2O / 6 h / Ambient temperature View Scheme

1: K2CO3 / acetone; dimethylformamide / 5.5 h / Heating 2: LiOH*H2O / tetrahydrofuran; H2O / 6 h / Ambient temperature View Scheme

1: 92 percent / zinc bromide / 2.5 h / Heating 2: 97 percent / K2CO3 / dimethylsulfoxide / 18 h / Ambient temperature 3: 94 percent / tetrabutylammonium hydroxide / methanol / 3 h / Ambient temperature 4: Et3N / 2 h / 6 °C 5: 81 percent / K2CO3, tris(3,6-dioxa-heptyl)amine / toluene / 6 h / Heating 6: 99 percent / aq. NaOH / methanol / 1.25 h / Heating 7: 2 N HCl View Scheme

1: 97 percent / K2CO3 / dimethylsulfoxide / 18 h / Ambient temperature 2: 94 percent / tetrabutylammonium hydroxide / methanol / 3 h / Ambient temperature 3: Et3N / 2 h / 6 °C 4: 81 percent / K2CO3, tris(3,6-dioxa-heptyl)amine / toluene / 6 h / Heating 5: 99 percent / aq. NaOH / methanol / 1.25 h / Heating 6: 2 N HCl View Scheme

1: Et3N / 2 h / 6 °C 2: 81 percent / K2CO3, tris(3,6-dioxa-heptyl)amine / toluene / 6 h / Heating 3: 99 percent / aq. NaOH / methanol / 1.25 h / Heating 4: 2 N HCl View Scheme

1: 94 percent / tetrabutylammonium hydroxide / methanol / 3 h / Ambient temperature 2: Et3N / 2 h / 6 °C 3: 81 percent / K2CO3, tris(3,6-dioxa-heptyl)amine / toluene / 6 h / Heating 4: 99 percent / aq. NaOH / methanol / 1.25 h / Heating 5: 2 N HCl View Scheme

1: 81 percent / K2CO3, tris(3,6-dioxa-heptyl)amine / toluene / 6 h / Heating 2: 99 percent / aq. NaOH / methanol / 1.25 h / Heating 3: 2 N HCl View Scheme

hydrogenchloride