Professor Sereda I have a question regarding stereochemistry of acid catalyzed hydration of epoxides. I know a carbocation is formed in the make-up intermediate and they are planar; however would the nucleophile add anti the the already present OH group? Or could attack from both sides since it is planar? (It can attack from either side, which is why the second step of anti-dihydroxylation should be performed in the absence of acids.  - GS).