1: 91 percent / Ag2O / CHCl3 / 20 °C 2: 19 percent / pyridine / 1.)3h, 45 deg C, 2.) 5d, 20 deg C View Scheme

1: 99 percent / n-butylbromide, Mg, CoCl2 / diethyl ether / 1.) 1h, 20 deg C 2.) 1h, reflux 2: 91 percent / Ag2O / CHCl3 / 20 °C 3: 19 percent / pyridine / 1.)3h, 45 deg C, 2.) 5d, 20 deg C View Scheme

in pyridine 1.)3h, 45 deg C, 2.) 5d, 20 deg C;