Pyrazolato-bridged polynuclear palladium and platinum complexes. Synthesis, structure, and reactivity

Keisuke Umakoshi; Yoko Yamauchi; Keiko Nakamiya; Takashi Kojima; Mikio Yamasaki; Hiroyuki Kawano; Masayoshi Onishi

doi:10.1021/ic026196g

Pyrazolato-bridged polynuclear palladium and platinum complexes. Synthesis, structure, and reactivity

Inorg Chem. 2003 Jun 16;42(12):3907-16. doi: 10.1021/ic026196g.

Authors

Keisuke Umakoshi¹, Yoko Yamauchi, Keiko Nakamiya, Takashi Kojima, Mikio Yamasaki, Hiroyuki Kawano, Masayoshi Onishi

Affiliation

¹ Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, Bunkyo-machi, Nagasaki 852-8521, Japan. kumks@net.nagasaki-u.ac.jp

PMID: 12793829
DOI: 10.1021/ic026196g

Abstract

Cyclic trinuclear complexes [Pd(3)(mu-pz)(6)] (1) and [Pd(3)(mu-4-Mepz)(6)] (2) and dinuclear complex [Pd(2)(mu-3-t-Bupz)(2)(3-t-Bupz)(2)(3-t-BupzH)(2)] (3) have been prepared by the reactions of [PdCl(2)(CH(3)CN)(2)] with pyrazole (pzH), 4-methylpyrazole (4-MepzH), and 3-tert-butylpyrazole (3-t-BupzH), respectively, in CH(3)CN in the presence of Et(3)N. In the absence of the base, treatment of [PdCl(2)(CH(3)CN)(2)] with pzH gave the mononuclear complex, [Pd(pzH)(4)]Cl(2) (6). The reaction of [PtCl(2)(C(2)H(5)CN)(2)] with pzH in the presence of Et(3)N under refluxing in C(2)H(5)CN afforded the known dimeric Pt(II) complex, [Pt(pz)(2)(pzH)(2)](2) (7). The protons participating in the hydrogen bonding in 3 and 7 are easily replaced by silver ions to give the heterotetranuclear complex [Pd(2)Ag(2)(mu-3-t-Bupz)(6)] (4) and the heterohexanuclear complex [Pt(2)Ag(4)(mu-pz)(8)] (5). The complexes 1-6 are structurally characterized.