1: 60 percent / α-chymotrypsin; aq. NH4OAc / dimethylformamide / 12 h / 20 °C 2: 79 percent / 10percent TFA / CH2Cl2 / 1 h / 20 °C View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: 96 percent / CuI; Et₃N / Pd(PPh₃)2Cl₂ / 4 h / 20 &deg;C<br />2: 79 percent / KF / dimethylformamide / 4 h / 20 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: 100 percent / NaOH / H₂O; dioxane / 0.5 h / 20 &deg;C<br />2: 96 percent / CuI; Et₃N / Pd(PPh₃)2Cl₂ / 4 h / 20 &deg;C<br />3: 79 percent / KF / dimethylformamide / 4 h / 20 &deg;C<br /> <br /> &nbsp;