1: pyrazolo[1,5-a]-pyridine With n-butyllithium in tetrahydrofuran T=-78°C; 2: formic acid ethyl ester in tetrahydrofuran T=-78°C; 0.5 h;

1.1: 86 percent / 40 percent aq. H2SO4 / 3 h / Heating 2.1: n-BuLi / tetrahydrofuran / -78 °C 2.2: 86 percent / tetrahydrofuran / 0.5 h / -78 °C View Scheme

1: NaCN; MnO2 / acetic acid / 3 h / 20 °C 2: aq. NaOH / 1 h / Heating View Scheme