The billionaire hedge fund founder announced a $10 million gift to Northwestern Medicine.
The historic Gold Coast has lost some of its most illustrious residents.
The measure would increase taxes on real estate transactions of $1 million or more.
Chicago has experienced high-profile defections of large corporations.
The mayor's plan to increase taxes on real estate transactions of $1 million and over was struck down.
The donors include the Crown and Pritzker family foundations.