On Sukhumvit between Sois 12 & 14 there is a smallish car-park which has slowly been transformed into open air beer-garden place, maybe with food available from the surrounding restaurants: Sunrise Tacos, V8 Diner, etc. They have just covered this area with a free-standing roof. Anyway, they had signs indicating they would be showing the Euro 2012 semi-final and final matches, and it looked like they had some large screen projection capability.
I am pretty sure all these matches kick-off at 01:45 BKK time.