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Updated: Jul 18, 2026

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library
Published on: June 20, 2014
Structure and reaction pathway of TMP-Zincate: amido base or alkyl base?
Masanobu Uchiyama1, Yotaro Matsumoto, Daisuke Nobuto
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. uchiyama@mol.f.u-tokyo.ac.jp
Abstract:
The novel directed ortho metalation (DoM) reagents for functionalized aromatic rings, TMP-Zn-ates (R2Zn(TMP)Li (R = Me, 1; tBu, 2)), have been reported to be synthetically useful for the chemo- and regioselective construction of multi-functionalized aromatic compounds. Here, we present the first comprehensive structural and mechanistic investigation by means of X-ray, NMR, and DFT studies on the DoM reaction employing our original TMP-Zn-ate base. The structures of TMP-Zn-ates in solution and in the solid state were determined. The DFT study strongly suggested that the deprotonation involving the TMP ligand on the TMP-Zn-ate is kinetically more favorable than that involving the alkyl ligand, and this view was supported by monitoring of the 13C NMR spectrum of the reaction mixture.
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