1: 95 percent / potassium phenylselenite, dipotassium hydrogen phosphate, 18-crown-6 / acetonitrile / 20 h / Heating 2: 65 percent / NaOH, TEBA / tetrahydrofuran / 5.5 h / Ambient temperature 3: 77 percent / silver(II) dipicolinate / benzene; H2O / Ambient temperature View Scheme