An X-ray investigation of stereoselectivity in the interactions of [Co(en) 3 ] 3+ with [Co(ox) 3 ] 3- (en is ethane-1,2-diamine and ox is oxalate).

The X-ray structure of racemic tris(ethane-1,2-diamine-κ 2 N,N')cobalt(III) tris(oxalato-κ 2 O 1 ,O 2 )cobaltate(III) pentahydrate, [Co(C 2 H 8 N 2 ) 3 ][Co(C 2 O 4 ) 3 ]·5H 2 O or [Co(en) 3 ][Co(ox) 3 ]·5H 2 O, has been determined. Hydrogen-bonding interactions along the C 3 -axis of the [Co(en) 3 ] 3+ cation with the [Co(ox) 3 ] 3- anion are heterochiral, while those perpendicular to this axis are homochiral. Implications for the interpretation of chiral discriminations and induction in electron-transfer reactions in solution are discussed.