Ironhide - killed by Sentinel Prime
Q - killed by Soundwave
Soundwave - killed by Bumblebee
Megatron - killed by Optimus
Sentinel Prime - killed by Optimus
Shockwave - killed by Optimus
Barricade - killed by Eps and his team
Wheelie and his friend - they die in one of the big spaceships as both are destroying it from the inside
Optimus gets his arm cut off by Sentinel Prime.
Carlie talks Megatron into fighting against Sentinel Prime which helps Optimus getting back up and kill both of them.
Starscream - killed by Sam