I believe the Alfa class submarines went this exact route. According to Sutton it had a crew complement of 32: http://www.hisutton.com/Alfa_Class_Submarine.html
Much more modern plans along similar design thinking is the SHELF reactor. It is designed to operates in an underwater, sealed capsule that is monitored and controlled remotely. Source: https://aris.iaea.org/Publications/smr-status-sep-2012.pdf