If you did that you would likely be fired. And for good reason.
Clojure is a language that needs a lot of careful thought before being dropped into a Java shop. It's the complete opposite of Java in many respects and at some point that code will need to be maintained.
This kind of sneaky sneaky subversion is how Linux gained a foothold in corporate IT. And we know how that turned out. This is definitely a method smart underlings can employ to change things for the better.
It is not without some career risks, but it can also open new doors.
I've known more than one developer who successfully did this in their Java job. They were not fired. Some of them ended up speaking at Clojure conferences about it.
Clojure is a language that needs a lot of careful thought before being dropped into a Java shop. It's the complete opposite of Java in many respects and at some point that code will need to be maintained.