NEW YORK CITY-In closing on its $252.5 million acquisition of the HarperCollins Building in Manhattan’s Plaza District, SL Green Realty Corp. has sold a 45% stake in the 37-story, 309,000-square-foot tower to the Canada Pension Plan Investment Board, the company unveiled Monday morning. Under the transaction, CPPIB has made an equity investment of $57.4 million before closing costs, adjustments and working capital.

The deal marks the second joint venture for SL Green and the Canadian-based investment management organization. Previously, the team partnered up to acquire Manhattan Tower at 600 Lexington Ave. for $193 million in May 2010, online property records show.

Peter Ballon, vice president and head of real estate investments-Americas at CPPIB, says in a statement that the company is “delighted” to acquire a significant interest in another “high-quality and extremely well-located property which has the potential to be repositioned as a top boutique office property in Midtown Manhattan.”