It might work but still I do not get it, why you have to block such domains. The links on adsense changes every time a new visitor visit your site. That mean if a black listed ads comes up on your page, next time it does not appear because they have a limited amount of how many time they will appear on the web.
From my side, I'm thinking are there another site that available if You block lot of website. I'm afraid there's no other site to be shown on your ads slot.