1.1: KNH(CH2)3NH2 / tetrahydrofuran / 15 h / 20 °C 1.2: 48 percent HF / acetonitrile / 20 °C 1.3: 45 percent / TFA; Et3SiH / benzene / 15 h / 20 °C 2.1: 80 percent / TFA; Pb(OTFA)4 / 0.5 h / 20 °C View Scheme