I doubt it'll be anytime this century, unless they make contact with us first. We just won't be advanced enough unless we make huge leaps and bounds in the areas of interstellar travel and communication. Which I guess is possible... But we certainly won't have faster than light travel by then as far as I can tell. We haven't even got close to light speed yet, or any known physics that would allow faster than light travel.
It also depends on what you mean by interaction. Do they have to let us know they're there? Cos if not, then we might be interacting with them already without us even knowing.