He was 53.
The president and COO of Mesirow Financial, Richard Price, said Tyree passed with his family nearby.
- Jim was truly one-of-a-kind; an amazing leader and great friend to so many. He made an indelible impression on each one of us at Mesirow Financial, and our hearts are broken. We will honor him by continuing his legacy and following the tenets that he taught us. Because of Jim's leadership, he has prepared us well to band together and get through this difficult time.
Words cannot express the sadness we feel. Our thoughts and prayers are with Eve, the kids and their entire family.
Mayor Richard Daley called Tyree a "wonderful Chicagoan and a dutiful civic leader who gave liberally of his time to improve the lives of others."
"As Chairman of the Board and former student of the Chicago City Colleges, he was a mentor to the students and a strong example of what can happen through hard work and perseverance," Daley said in a statement.
Mayor-elect Rahm Emanuel expressed similar sentiments.
"His service as Board Chairman of City Colleges, his work with non-profit organizations like the Juvenile Diabetes Research Foundation, and his investment in the Sun-Times made him a pillar of our city's civic life. He and I worked together on many important initiatives like combating diabetes and supporting stem cell research. He will be missed," said Emanuel.
Tyree grew up in Chicago's Beverly neighborhood. He earned his bachelor's and MBA degrees from Illinois State University, according to his biography on Mesirow Finacial's website.
With his partners, Tyree became the Chicago Sun-Times' fourth owners when they purchased it and more than 50 suburban publications in October 2009.
"I wouldn't be here if I didn't believe that this organization can maintain a strong business model and be profitable," he said at the time.
He is survived by his wife, Eve, a daughter, Jessica, and twin sons, Matthew and Joseph.