Benzene --- H2SO4/HNO3, heat ---> 1,3-dinitrobenzene --- Sn/HCl ---> 1,3-diaminobenzene --- NaNO2/HCl, 0°C; CuBr ---> 1,3-dibromobenzene --- Mg/THF(anh.); 2eq. acetaldehyde; H3O+ ---> desired product
The difficult part is making the 1,3-dibromobenzene, but then is one step since the side chains are symmetric.