SL Green to kick off collections at 510 Mad.

510 Madison Avenue, Harry Macklowe of Macklowe Properties (top) and Marc Holliday of SL Green (bottom)

Despite Macklowe Properties’ bid for an extension on a $185 million loan at 510 Madison Avenue, SL Green Realty has plans to begin collection proceedings on the loan March 1, according to Crain’s. SL Green had bought the loans associated with 510 Madison Avenue from Union Labor Insurance toward the end of last year, in what many saw as a move to take over the building. SL Green took a similar strategy at 100 Church Street, the one-time property of the Sapir Organization, which it took over through its role as debt holder last month. While SL Green is remaining mum on the 510 Madison building, Stephen Meister, a Macklowe attorney, said his company will “take prompt legal action” if SL Green doesn’t allow the loan extension.