David Wheeler, a towering figure in the history of Boston theater, died today at the age of 86. As artistic director of the Theatre Company of Boston from 1963 to 1975, Wheeler worked with such young actors as Al Pacino, Dustin Hoffman, Robert DeNiro, Stockard Channing, Blythe Danner, Jon Voigt, and Robert Duvall early in their careers, before they went on to stardom. “I had five Academy Award winners almost right in a row,’’ he told the Globe last April. At Harvard University, his students included Matt Damon, who took his Introduction to Theater Arts class, as well as a directing class.