Cleavage of the dimeric cyclopalladated [Pd(N,C-dmba)([mu]-X)]2, (dmba = N,N-dimethylbenzylamine; X = SCN and NCO) by diphosphines. Palladium(II) compounds with distinct structures in the solid-state and in solution

• Published in: Transition metal chemistry (Weinheim) Vol. 26; no. 4-5; p. 570
• Main Authors: Ananias, Sandra R, Mauro, Antonio E, de Lucca Neto, Vicente A
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.08.2001
• ISSN: 0340-4285; 1572-901X
• DOI: 10.1023/A:1011056829642

The reactions of the pseudohalide-bridged dimer [Pd(N,C-dmba)(μ-SCN)]^sub 2^ (1) (dmba = N,N-dimethylbenzylamine) with cis-Ph^sub 2^PCH=CHPPh^sub 2^ (cis-dppet) (1:1 molar ratio) and of [Pd(N,C-dmba)(μ-NCO)]^sub 2^ (2) with Ph^sub 2^PCH^sub 2^CH^sub 2^PPh^sub 2^ (dppe) (1:2 molar ratio) gave mononuclear [Pd(C-dmba)(SCN)(cis-dppet)]·H^sub 2^O (1a) and [Pd(C-dmba)(NCO)(dppe)] (2a), respectively, with the diphosphines acting as chelating ligands. Reaction of (2) with Fe(C^sub 5^H^sub 4^PPh^sub 2^)^sub 2^ (dppf) (1:1 molar ratio) yielded [{Pd(N,C-dmba)(NCO)}^sub 2^(μ-dppf)] (2b), a bimetallic species containing two palladium atoms bridged by the diphosphine, whereas reaction in a 1:2 molar ratio gave the mononuclear [Pd(N,C-dmba)(dppf)][NCO]·CH^sub 2^Cl^sub 2^ (2c), with the diphosphine acting as a chelating ligand. The compounds have been characterized by elemental analysis, i.r., ^sup 31^P{^sup 1^H}, ^sup 13^C- and ^sup 1^H-n.m.r. spectroscopies. Conductivity measurements together with spectroscopic data showed that (1a) and (2a) do not have the same structure in the solid state and in MeCl solution, whereas for compounds (2b) and (2c) no structural changes were observed when the solids were dissolved in MeCl.[PUBLICATION ABSTRACT]