Economics concerns itself with voluntary, win-win exchanges among actors that increase overall wealth. Economics depends upon property rights.
Politics concerns itself with rights to choose, refuse or oblige. Rights imply the ability to force others into action (or prevent them from acting), which translates into non-voluntary (compulsory), zero-sum transfers of wealth (or its equivalent) from those with less power to those with more power.
Power can be exchanged into wealth but wealth cannot always be exchanged into power.