Synthesis of Ag⁺-Selective Dipalladium(II) Metallohost Based on O-Alkyloxime Bis(N₂SO) Ligands

Abstract

Novel bis(N₂SO) ligands 2a (= H₄L^2a) and 2b (= H₄L^2b) comprising O-alkyloxime, thiophenol, and phenol moieties were synthesized. The complexation of H₄L^2a and H₄L ^2b with palladium(II) acetate afforded the dinuclear metallohosts [L ^2a Pd₂] and [L ^2b Pd₂], which have a recognition site consisting of two sulfur and four oxygen donor atoms. The metallohost [L^2bPd₂] strongly binds Ag⁺ to give [(L^2bPd₂)₂Ag]⁺, whereas no detectable interaction between [L^2bPd₂] and hard metal cations (Na⁺, Ca²⁺, Y³⁺, La³⁺, and Lu³⁺) was observed.

Keywords:

• Metallohost
• oxime
• palladium
• silver
• thiol

Acknowledgments

Dedicated to Professor Naomichi Furukawa on the occasion of his 70th birthday. This work was supported by Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, Japan.