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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Structural and coordination studies of "pearl oysterlike" porphyrins
Zakaria Halime1, Mohammed Lachkar, Thierry Roisnel
1Ingénierie Chimique et Molécules du Vivant, Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1, Rennes Cedex, France.
Abstract:
We report the coordination studies of porphyrins with pre-organized but yet flexible straps, each bearing over the center of the porphyrin either a 2,2-malonic acid diethyl ester residue or a 2,2-malonic acid residue. The straps are attached to the porphyrin via two adjacent meso positions, 5,10 and 15,20, respectively, and the 2,2-malonic acid diethyl ester groups are connected to the straps on benzylic carbon atoms. These two structural features allow a significant flexibility of the straps, as confirmed by the comparison of the X-ray structures of the zinc, nickel, and lead complexes of porphyrin 1. In the latter, the influence of the lone-electron pair of lead is clearly demonstrated. The coordination of bismuth is also reported.
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