All IMHO: sanctions will not change Putin's situation, that's going to have to come from within Russia as a result of their internal politics. Supposedly, at least on paper, they still have "free" elections and the people vote for their leaders.
Putin knows this very well. It's one reason that bit by bit, very gradually over the years, he's deliberately guiding his country towards the old Soviet model and away from the West.
All that is needed to make a happy life is within yourself, in your way of thinking. -Marcus Aurelius