trimethylsilyl trifluoromethanesulfonate in dichloromethane 3 h; Ambient temperature;

in ethanol T=20°C; aza-Michael addition; 24 h;

1: 90 percent / 37.5percent NaOH / H2O; benzene / 1 h / Ambient temperature 2: 42 percent / trimethylsilyl triflate / CH2Cl2 / 3 h / Ambient temperature View Scheme