Combining Future[List] objects

I have the following code say
val l1 = List("ip1", "ip3", "ip2")
val l2 = Future{List(20,35,21}
I need to find the maximum value in l2 which in this casxe is 35, and since it has index of “1” in the l2 list, I want to fetch the element that is at index “1” in list l1

How do I do this?

Something like this?

scala> l2.map(_.zip(l1).maxBy(_._1)._2)
res9: scala.concurrent.Future[String] = Future(<not completed>)

scala> res9
res10: scala.concurrent.Future[String] = Future(Success(ip3))