Spontaneous formation of water-soluble rhodium quinone catalysts

ORGN 563

Marcus D. Faust Jr., Sang Bok Kim, Julia L. Barkin, William C. Trenkle, trenkle@Brown.edu, and Dwight A. Sweigart, Dwight_Sweigart@Brown.edu. Department of Chemistry, Brown University, Box H, Providence, RI 02912
Organometallic rhodium complexes are widely utilized in catalysis. Herein we report the formation and NMR study of the pi-bonded rhodium hydroquinone complex 1. This species reacts with water to liberate the hydroquinone, but in the presence of aqueous base is rapidly deprotonated to afford the very stable quinone complex 2, which has been shown to be an effective multifunctional catalyst in certain C-C coupling reactions. The stability of the quinonoid complex 2 is demonstrated by the remarkable reaction of insoluble rhodium dimers [Rh(COD)X]2 (X = OH-, Cl-) with aqueous hydroquinone dianion (3) to generate 2 under mild conditions.

 

Physical Organic Chemistry, Metal-Mediated Reactions, Asymmetric Reactions and Syntheses
8:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Organic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007