Two partners who were with Chicago boutique firm Stetler, Duffy & Rotert Ltd. when it was founded about 19 years ago have joined the litigation group at the Chicago office of Loeb & Loeb LLP.Loeb announced on Monday that white-collar defense attorneys Joseph J. Duffy and Corey Rubenstein have joined the firm from Stetler, where Duffy was a founding principal. Duffy’s former firm is now called Stetler & Rotert Ltd.Duffy is known in part for his work representing former ex-Gov. Rod Blagojevich’s adviser and …