triphenylphosphine; diethylazodicarboxylate in tetrahydrofuran 2.5 h; Ambient temperature;

1: 97 percent / sodium borohydride / methanol / 1.) 0 deg C, 30 min, 2.) room temperature, 1 h 2: 58 percent / triphenylphosphine, diethyl azodicarboxylate / tetrahydrofuran / 2.5 h / Ambient temperature View Scheme