Why are fluorides of transition metals unstable in low oxidation states?
I would think that since fluorine and oxygen are highly electronegative, it's obvious that they be stable at high oxidation states. However, $\ce{Cl}$ is also highly electronegative, but it does exist in low oxidation states with transition metals.
For example $\ce{CuCl}$ exists but not $\ce{CuF}$ and $\ce{TiCl2}$ exists but not $\ce{TiF_{2}}$. Why is it so?
Fluorides of transition metals unstable in low oxidation states
This is the statement given in my high school chemistry text book but no explanation provided. I am interested to know the reason for it.