I do not know about a free code review tool with Eclipse (except some in development, , or plugins like Jupiter, both not taking into account Telelogic products).
All those tools are generally based on Eclipse Mylyn plugin, and even a commercial product like TaskTop Enterprise (199$ for one user, Note: I am not associated with that product) don't have a Telelogic Synergy connector yet.
They do have a connector to another non-freeware software: Atlassian Jira-Crucible, which offer a lot of code review features. But again: not free...