Move gameobject to button in new 4.6?

I'm trying to figure out a way to move a gameobject underneath a new UI button, here is my current script:

 public Button button;
 
 Vector3 positioning = Camera.main.ScreenToWorldPoint(button.transform.position);
 this.transform.position = Vector3.Lerp(this.transform.position, positioning, Time.deltaTime * 5);

however I'm having it trouble getting it working(it moves to an incorrect position, notably x/y), does anyone know how I would do this? I'm using c# but converting from javascript is easy