Chicago-based Old Second Bancorp, Inc. has bolstered its commercial banking business team with addition of three executives formerly with MB Financial (now Fifth Third Bank).

Donald J. Clark has been named Senior Vice President, Commercial Banking, with Old Second National Bank. He will be responsible for developing and growing commercial banking, specializing in the senior housing and healthcare space. 

Clark has over 30 years of commercial banking and financial services experience. Prior to joining Old Second, he served as Managing Director, Senior Vice President, with the National Healthcare Banking Group of MB Financial). Clark received a bachelor's degree in finance at Roosevelt University.

Louis L. Weinzelbaum has been named Group Market President, Senior Managing Director, with Old Second National Bank. Weinzelbaum will be responsible for developing and growing commercial banking business and leading the Professional Services practice. This includes assembling teams of seasoned commercial banking experts in commercial, industrial and professional service businesses, while also marketing Old Second's full suite of financial products to customers and prospects.

Weinzelbaum has more than 30 years of commercial banking experience in Chicagoland and national markets. Prior to joining Old Second, he served as Commercial Group President with MB Financial, leading the Professional Services business. He earned his bachelor's degree in political science and history at Southern Methodist University, Dallas, TX.

Alan H. Kohn has been named Group Market President, Senior Managing Director, with Old Second National Bank. He will be responsible for expanding Old Second's national healthcare business line and augmenting well-established middle market commercial banking business.  Included in this effort will be recruiting seasoned commercial bankers with expertise in senior housing and other healthcare related industries, in addition to marketing the bank's full suite of financial products.

Kohn has over 30 years of commercial banking experience in the Chicagoland markets. Prior to joining Old Second, he served as Senior Managing Director with MB Financial Bank in its National Healthcare Banking Group. He also served as Managing Director of The PrivateBank (now CIBC). Kohn earned his bachelor's degree in finance and insurance from the University of Iowa, as well as a degree from the Pacific Coast Banking School at the University of Washington.

Old Second Bancorp, Inc. is a diversified bank holding company headquartered in Aurora, IL. Its business banking includes equipment finance, small business banking, online and mobile banking, and commercial banking.