Method B. A mixture of 9'g.(0.036 mole) of the tetra-hydro-l, 4naphthalenediacetic acid and 52 ml. of thionyl chloride was warmed carefully until the evolution of sulfur dioxide had ceased (15 min.). After removal of the excess thionyl chloride in vacuo, a solution of the residual acid chloride in 100 ml. of redistilled nitrobenzene was added with stirring over a period of 2 hr. to a cold (a') solution of 19 g.(0.145 mole) of anhydrous aluminum chloride ...
