The nearly 1,400-foot tower at 432 Park Avenue, briefly the tallest residential building in the world, was the pinnacle of New York's luxury condo boom half a decade ago, fueled largely by foreign buyers seeking discretion and big returns.

Donald Tober, CEO and co-owner of the New York-based Sugar Foods, leapt to his death just after 5 a.m., and was found in the courtyard of the luxury, Upper East Side building between 65th and 66th streets, the sources said.