Sanctions are the goal. That's the hope, that oligarchs—one of the pillars of Putin's regime—could be his downfall if they calculate that not only sanctions but a longer-term, cold war, iron curtain type of situation will basically cut them off from their assets in the West. This is, right now, the goal.
The problem, though, is that the second pillar of the Russian regime right now is the security service, the former KGB. That pillar is less affected by sanctions because they don't have the sizable assets. I'm sure they have mansions abroad as well, but their loyalty to the regime has a different source. It's not the regime allowing them to enrich themselves, which is the source of loyalty for the oligarchs.
It would be harder to break and to crack that part through sanctions. The conditions—