When Alfred Werner was developing the field of coordination chemistry, it was argued by some that the optical activity he observed in the chiral complexes he had prepared was due to the presence of carbon atoms in the molecule. To disprove this argument, Werner synthesized a chiral complex of cobalt that had no carbon atoms in it, and he was able to resolve it into its enantiomers. Design a cobalt(III) complex that would be chiral if it could be synthesized and that contains no carbon atoms. (It may not be possible to synthesize the complex you design, but we will not worry about that for now.)

Chirality is a property of molecules where a molecule and its mirror image are non-superimposable, similar to left and right hands. Chiral molecules have one or more centers of chirality, usually a stereogenic carbon atom is involved with four different substituents (i.e., groups attached to the atom). However, metal complexes can also exhibit chirality, even though they may not contain stereogenic carbon atoms. A chiral metal complex typically involves a coordination number of four or higher.

A cobalt(III) complex refers to a metal complex containing a central cobalt ion in the oxidation state of +3, Co(III), bonded to other atoms or groups, which are known as ligands. The coordination number is the number of bonds between the central ion and its ligands.

Since the desired complex must have no carbon atoms, we will focus on creating a chiral cobalt(III) complex with halide ligands or other inorganic ligands. Remember, the coordination number must be four or higher for the complex to exhibit chirality. In this context, the octahedral geometry (coordination number 6) seems to be the most suitable geometry. A possible chiral cobalt(III) complex to be synthesized would be [Co(NH3)3Cl3]. In this complex, the central cobalt(III) ion is bonded to three ammonia ligands (NH3) and three chloride ligands (Cl-). Overall, the complex is a neutral octahedral species and is chiral due to the different arrangement of NH3 and Cl- ligands around the cobalt center. Please note that the complex is hypothetical and may not be synthesized in reality.

It could be helpful to draw the structure of the chiral [Co(NH3)3Cl3] complex, emphasizing the octahedral arrangement of the ligands. To visualize the chirality, you can draw both enantiomers, non-superimposable mirror images. In conclusion, a possible chiral cobalt(III) complex that contains no carbon atoms is [Co(NH3)3Cl3]. This complex exhibits chirality due to different spatial arrangements of NH3 and Cl- ligands around the central cobalt ion.