@OP, We can put the question of a side-reaction on the back burner for now. Yes, I think you need a catalyst of some kind, and an acid catalyst is the first thing that comes to mind. What is your intended use of the product?
@Meter, I think that a Fischer esterification would probably work, especially with a large excess of ethanol. The side reaction might not be a significant problem. The existence of the product suggests that the side reaction can be avoided or minimized.