Long Story Short: Not as such
Round 1: You cast haste. So far, so good, though I would then recommend using the extra action provided to make a weapon attack, boosted by Divine Smite if you wish.
Round 2a: Cast green-flame blade, using your Divine Smite for extra damage. So far, so good.
Round 2b: Extra attack from haste, Divine Smite for extra damage. Still working out fine.
Round 2c: Drop haste concentration to cast thunderous smite and attack. No can do. After dropping concentration on haste, the formerly hasted creature cannot move or take actions until after its next turn. While you can cast thunderous smite using a bonus action, you cannot make further attacks this turn, having consumed your extra hasted action, nor can you attack next round, due to the fallout from dropping haste. What this also means is that you cannot drop concentration in the middle and then cast/attack with thunderous smite, as the lack of actions start as soon as haste wears off.
Round 3: Can’t do anything of note due to the haste fallout, though you may maintain concentration on thunderous smite should you choose.
Round 4: You can finally make an attack to release that thunderous smite you’ve been holding onto.
Tl;dr: Just keep haste up and either multi-attack or green-flame blade and haste attack each turn, it’ll do more total damage. And it will also avoid wasting a 3rd level slot on what ends up being a 1-turn thing.