Haloalkanes And Haloarenes

1-phenyl-1, 3-dibromopropane on treatment with alc. KOH givens diastereomeric mixture in which compound (A) is major product. (A) gives the following reaction

(A) \(\buildrel {AlC{l_3}/\Delta } \over \longrightarrow\) (B) \(\buildrel {:CuBr} \over \longrightarrow\) (C) + (D)

Compound (C) and (D) are