The production and decay properties of an isotope of the 112th element, 277Cn, were investigated using a gas-filled recoil ion separator by irradiation of 208Pb targets with 70Zn beams at 347.5, 351.5, and 355.5 MeV. The excitation function for this reaction was measured for the first time. We observed one decay event assigned to the decay of 277Cn at the beam energy of 351.5 MeV. The measured production cross section was 0.078+0.179 pb. The present result gives improved half-lives of 0.61+0.46 and 0.19+0.14 ms for 277Cn and 273Ds, respectively. At the other energies, no event was observed. The measured upper cross section limits were 0.25 and 0.15 pb at the beam energies of 347.5 and 355.5 MeV, respectively.