When to use bis, tris, etc.

[LaurenAkason2A]

Hi! When naming coordination compounds, I'm having a hard time figuring out how to name molecules with bis, tris, etc. I don't really understand how it works. Could someone give me some tips?

[Abby 2B]

hi! In lecture, Professor Lavelle said we use prefixes like bis, tris, etc. when there is already a prefix (bi-, tri-, etc.) on the ligand that we are naming.

[Jessica Arcos 2H]

Hi! You would use the prefixes bis-, tris-, tetrakis-, etc. when there are multiple polydentate ligands. For example, diethylenetriamine, shown as (dien), is a tridentate ligand so you would name it bisdiethylenetriamine when there's two of them, it would shown as (dien)2. You wouldn't use the prefix if there's only one (dien) ligand.

[Mia Orr 3B]

We use prefixes such as bis-, tris-, tetrakis-, pentakis-, etc when a ligand name already has the prefixes di-, tri-, tetra-, etc or when the ligand is polydendate.

[Albert Chen 1G]

You should use these prefixes when a greek prefix already exists in the naming. For example, for the dichlorobis(ethylenediamine)cobalt(III) ion, the bis is added because di is already added to -amine to for diamine. So, the prefix bis is used.