1: 83 percent / pyridine / Ambient temperature 2: 77 percent / t-butylamine / methanol / 0.33 h / Ambient temperature 3: 93 percent / Ag2O / 7 h / Ambient temperature 4: 86 percent / zinc powder, acetylacetone / pyridine / 0.25 h / Ambient temperature 5: 69 percent Spectr. / potassium fluoride, tetraethylammonium chloride / acetonitrile; H2O / 0.5 h / 53 °C View Scheme