1: NaNO2 / aq. HCl / 1 h / 60 °C 2: 78 percent / chromic anhydride, H2SO4, H2O / acetone / 1 h / Ambient temperature View Scheme

<b>Multi-step reaction with 3 steps<br /> </b>1: CH₃COONH₄ <br />2: 65 percent / TFA / 3 h / Heating<br />3: HCl<br /> <br /> &nbsp;