1: 63 percent / N,N'-dicyclohexylcarbodiimide, 1-hydroxybenzotriazole, N-ethylmorpholine / CH2Cl2 / -15 deg C, 1 h -> room temperature, 5 h 2: trifluoroacetic acid / 0.5 h / Ambient temperature View Scheme

trifluoroacetic acid 0.5 h; Ambient temperature;