I think it depends on where you want ya'lls relationship to go.
You say you want him to be single, presumably so that he may end up with you. But he has his eyes set on someone else, and so long as he does, he won't pursue you /: My question to you is, does he know that you like him? Maybe he doesn't realize that you do. Many times when people learn that another person likes them, they begin to look at that person in a different light, one that they hadn't looked at them in before- a more romantic one. He may not show interest in you because you haven't shown your interest in him :)
The second part to that is weather you should help him get with someone other than yourself. Well, are you okay with just being friends with him? Really think about it! Will you be okay on the inside seeing the guy you like with some other girl, or will it end up hurting you? And will it hurt you even more knowing that you helped in making sure he was taken, and not available for you to get to know him romantically? Maybe you are, but its just questions you need to ask yourself before getting him with another girl.
You need to put your happiness before his, because you are the most important person in your life! Realistically, if you don't help him get with this girl, he won't be unhappy one way or another. He'll either simply stop pursuing her or find another way to, no skin off his back. But if you help lock yourself out of his love life by helping him get with her, you may be causing your own unhappiness. And you would miss a valuable opportunity of telling him how you feel, and possibly sparking something in him for you!
My advice is to not try to set him up with her, because it seems that isn't what you ultimately want to happen. From there, you have the choice of not telling him how you feel and staying friends, or take the leap of faith and tell him why you don't want to help him (because you want him to be with you, not her!) and potentially starting something new and exciting! (:
(sorry for the book, this is the first question I've answered ^-^; I hope its helpful!)