Synthesis, Structure, and Function of PCP Pincer Transition-Metal-Complex-Bound Norvaline Derivatives

Abstract

A PCP pincer palladium-complex-bound norvaline, Boc-l-[Pd]Nva-OMe, was synthesized and fully characterized by NMR, FT-ICR-MS, and X-ray crystallography. Selective N- and C-terminus transformations of Boc-l-[Pd]Nva-OMe were performed by conventional deprotection–condensation procedures to afford lipophilic palladium-bound norvaline derivatives without metal detachment. The N-/C-bisfunctionalized palladium-bound norvaline showed self-assembly properties, as evidenced by supramolecular gel formation. The catalytic activity of the supramolecular gel was assessed in the 1,4-conjugate addition of phenylboronic acid.

Keywords

amino acids - cross-coupling - catalysis - palladium - self-assembly

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