Kenneth J. Witkin will step in this September to become the new president and CEO of CBRE Realty Finance Inc. in Hartford, taking the reins from interim leader Ray Wirta. Previously, Witkin was executive vice president in the commercial real estate banking group of Bank of America, with more than 25 years in the real estate finance industry. He is a member of the Urban Land Institute, Real Estate Roundtable and the International Council of Shopping Centers. CBRE has been trying to find a new CEO since April, when its previous head, Keith Gollenberg, left the company.