I purchased a 5 set accent light 120v halogen accent lights. Can I put them on a regular single pole wall switch without a transformer?

Why do you ask "without a transformer"?

If the lights are 120 volts, then a transformer is not needed at all.

Are the lamps rated 120 volts?

If they are not 120 volts, then a transformer is needed. The 120 volt switch can control the input of the transformer to switch the low voltage lights.