map! not working in command mode

I want to use ;; instead of <Esc> to return to normal mode. I want ;;
to work everywhere <Esc> works, e.g. insert mode, command mode, visual
mode.

So, I did these mappings:

map! ;; <Esc>
map ;; <Esc>

But in the command mode I am having trouble. For example, if in the
command I type

:set list;;

It executes the command :set list instead of escaping to normal mode.
How to fix this?