The Vitesse Arnhem star also insists he was a target of Celtic in the summer window.
He said: "There was a lot of interest in me this summer. Vitesse wanted me to stay for three years and clubs like Celtic, Spal, Fenerbahce and Apoel Nicosia all made their interest known.
"In fact, just this week before I agreed to sign for the Revs, Rangers and Stoke City tried to sign me.
"Look, I am going to a league with the likes of Zlatan Ibrahimovic and Wayne Rooney in it. It's a great standard and I can't wait to play in America."
Buttner played at Manchester United for two seasons after joining from Vitesse in 2012. He made just 28 appearances across the two campaigns before leaving for Dynamo Moscow.