I think the following would work,
Clevland get Koufas
Cetics get Prince, Adams, 2015 memphis 1st (from clevelnd) (top-five protected and 15-30 protected through 2016, top-five protected in 2017 and 2018, unprotected in 2019) from the Memphis Grizzlies (maybe memphis lifts the restriction as part of trade), and Cs get back their 2016 2nd rd pick maybe also pilage both teams players they have the rights to in europe the Grizz have a 22yr old SF Timma and Cavs have two PFs who look interesting Karaman and Macvan.
Memphis gets Green and Bass
The Cavs get the big the desperately need and he is young so he might be a long term solution
The Grizz upgrade talent at 3 and 4. This makes them smaller inside then I image they would like but talent is talent
The Cs move two player not likely to be with the team next year. Prince becomes a buyout canidate. Adams has some potential to develop. The pick adds to the stock pile. This cleans up the big man rotation and give Young a chance to earn some minutes at the 3.
Cap wise this may involve a few tweeks namely a small amount of salary needing to be removed from Memphis. Calathes may also need to go to boston to make it work.