This seems like a bad idea from a business value perspective. What value is delivered by translating mountains of code? Probably none, being honest.
As I am also partially Java guy, I came to conclusion that migration of project into JRuby and then embedding Clojure parts gradually might ease the transition.
Don't transition everything, giant waste of time. Run ruby/rails on jruby, then package the core Clojure logic up as a library, and call into it from rails where needed. Clojure is your core logic, ruby/rails is the web front end to that core.
We're growing to the point of needing a few distinct components after building a Rails monolith that already had very strong internal boundaries. As we split out different parts to run on different machines, they will either get an immediate re-write, or eventual re-write from behind the service interface.