potassium hydroxide; water in 1,4-dioxane Heating / reflux;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / 1.5 h / -80 &deg;C<br />1.2: 5 h / -80 - 10 &deg;C<br />2.1: lithium chloride; N-ethyl-N,N-diisopropylamine / acetonitrile / 16 h / 20 &deg;C<br />3.1: palladium 10 on activated carbon; hydrogen / ethyl acetate / 48 h<br />4.1: potassium <i>tert</i>-butylate / tetrahydrofuran / 1 h / |Reflux<br /> <br /> &nbsp;