The Academy of Television Arts & Sciences announced Tuesday that Mischa Barton of “The O.C.,” Jimmy Kimmel of “Jimmy Kimmel Live” and Chris Noth of “Sex and the City” will be among the presenters at the 56th Annual Primetime Emmy Awards, set for Sept. 19 at the Shrine Auditorium in Los Angeles. The show will be broadcast live on ABC at 8 p.m. (ET).