1.1: NaNH2 / dimethylformamide / 2 h / 20 - 80 °C 1.2: 47 percent / dimethylformamide / 4 h / 20 - 80 °C 2.1: 74 percent / aq. NaOH / ethanol / 24 h / Heating 3.1: 90 percent / polyphosphoric acid / 0.33 h / 110 °C 4.1: 20 percent / tetrahydrofuran; toluene / 3 h / Heating View Scheme

1: 90 percent / polyphosphoric acid / 0.33 h / 110 °C 2: 20 percent / tetrahydrofuran; toluene / 3 h / Heating View Scheme

1: 74 percent / aq. NaOH / ethanol / 24 h / Heating 2: 90 percent / polyphosphoric acid / 0.33 h / 110 °C 3: 20 percent / tetrahydrofuran; toluene / 3 h / Heating View Scheme

1.1: NaNH2 / dimethylformamide / 2 h / 20 - 80 °C 1.2: 47 percent / dimethylformamide / 4 h / 20 - 80 °C 2.1: 74 percent / aq. NaOH / ethanol / 24 h / Heating 3.1: 90 percent / polyphosphoric acid / 0.33 h / 110 °C 4.1: 20 percent / tetrahydrofuran; toluene / 3 h / Heating View Scheme

in tetrahydrofuran; toluene Grignard reaction; 3 h; Heating;