Best I could do
Boston - Lowry
Toronto - Gay, Arthur
Memphis - Davis, Fields, Lee, Kleiza, Bos 1st (protected top 20, top 15 next year, top 10 2015, unprotected 2016), Bos 2nd
Boston gets a quality PG replacement and shaves a bunch of salary for a redundant wing and a heavily protected 1st (and a 2nd).
Toronto gets Gay and Arthur, two players they want for Davis and some now redundant wings.
Memphis saves a bunch of money long term, gets a nice young PF prospect, and adds a bunch of depth and a future pick (and a 2nd).