di-isopropyl azodicarboxylate; triphenylphosphine in tetrahydrofuran T=60°C;

1.1: n-BuLi / hexane; tetrahydrofuran / 1 h / 23 °C 1.2: 93 percent / tetrahydrofuran; hexane / 0.5 h 2.1: 100 percent / HCl / ethanol; H2O / 20 h / 23 °C 3.1: 52 percent / triphenylphosphine; diisopropyl azodicarboxylate / tetrahydrofuran / 60 °C View Scheme

1: 100 percent / HCl / ethanol; H2O / 20 h / 23 °C 2: 52 percent / triphenylphosphine; diisopropyl azodicarboxylate / tetrahydrofuran / 60 °C View Scheme