A sterochemical challenge

Mar 2014
Hi i was wondering if anyone could help me with this question,

From the addition of iron fillings, sulphuric acid and ethylenediamine a racemic mixture of chiral complexes can form but when a similar experiment of hydrochloric acid, copper fillings and ethylenediamine are mixed a racemic mixture is not formed. Please use balanced equations to demonstrate this.

- So far i have concluded that the ethylenediamine chelates the fe2+ ions so chiral complexes can be formed as ethylenediamine is bidendrate. from the equation:

Fe2+ + (NH3)2C2H2 + 2H2SO4 ---> FeC2H4(NH3)2(SO4)2H2O

However, i cannot see why it does not work for copper and hydrochloric acid.

Any help would be much appreciated :)