(oxidation);

1: methyllithium With copper(l) iodide in tetrahydrofuran; ethylene glycol dimethyl ether T=-78 - 0°C; 0.333333 h; 2: C8H6BrClO2 in tetrahydrofuran; ethylene glycol dimethyl ether T=-78°C; 0.666667 h;

in N,N-dimethyl-formamide Heating;