1: With trimethylsilyl bromide; phosphorous acid trimethyl ester in toluene T=110°C; 3 h; 2: With methanol in dichloromethane 24 h;

1: acetic anhydride With orthophosphorus acid T=0 - 20°C; 2: N-benzylidene-α,α-diphenylbenzylamine T=0°C; 3: With hydrogenchloride; water 8 h; Reflux;

1: CHCl3 / 12 h / Ambient temperature 2: 1 M HCl in MeOH / 0.25 h / Heating View Scheme