Media type: E-Article Title: The First Metal Complexes of the Proton Sponge 1,8‐Bis(N,N,N′,N′‐tetramethylguanidino)naphthalene: Syntheses and Properties Contributor: Wild, Ute; Hübner, Olaf; Maronna, Astrid; Enders, Markus; Kaifer, Elisabeth; Wadepohl, Hubert; Himmel, Hans‐Jörg imprint: Wiley, 2008 Published in: European Journal of Inorganic Chemistry Language: English DOI: 10.1002/ejic.200800677 ISSN: 1099-0682; 1434-1948 Keywords: Inorganic Chemistry Origination: Footnote: Description: <jats:title>Abstract</jats:title><jats:p>In this work we report on the syntheses and properties of the first transition metal complexes of the proton sponge 1,8‐bis(<jats:italic>N</jats:italic>,<jats:italic>N</jats:italic>,<jats:italic>N′</jats:italic>,<jats:italic>N′</jats:italic>‐tetramethylguanidino)naphthalene (btmgn). Of the three complexes [(btmgn)PdCl<jats:sub>2</jats:sub>], [(btmgn)PtCl<jats:sub>2</jats:sub>] and [(btmgn)PtCl<jats:sub>2</jats:sub>(C<jats:sub>2</jats:sub>H<jats:sub>4</jats:sub>)], the first two feature a chelating btmgn ligand that is bound to the metal atom through two nitrogen atoms. Only one metal–N bond is established in [(btmgn)PtCl<jats:sub>2</jats:sub>(C<jats:sub>2</jats:sub>H<jats:sub>4</jats:sub>)]. The molecular structures of [(btmgn)PdCl<jats:sub>2</jats:sub>] and [(btmgn)PtCl<jats:sub>2</jats:sub>] show some interesting details. X‐ray crystallographic studies reveal that the naphthyl aromatic systems in both complexes are not planar, the metal atoms reside above the “best‐plane” of the naphthyl systems and the compounds adopt a chiral conformation in the crystalline phase. Several dynamic processes of the two guanidinyl groups in solution were identified by line‐shape analysis of the temperature‐dependent NMR spectra. The complex [(btmgn)PtCl<jats:sub>2</jats:sub>(C<jats:sub>2</jats:sub>H<jats:sub>4</jats:sub>)] eliminates ethylene at elevated temperature to give [(btmgn)PtCl<jats:sub>2</jats:sub>]. Quantum chemical (DFT) calculations indicate that the Δ<jats:italic>G</jats:italic><jats:sup>0</jats:sup> value for this reaction is close to zero. Indeed the compound [(btmgbp)PtCl<jats:sub>2</jats:sub>] {btmgbp = 2,2′‐bis(<jats:italic>N</jats:italic>,<jats:italic>N</jats:italic>,<jats:italic>N′</jats:italic>,<jats:italic>N′</jats:italic>‐tetramethylguanidino)biphenyl} in which the naphthyl group is replaced by a biphenyl group is not amenable to ethylene elimination. First experiments point to interesting catalytic properties of the new complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)</jats:p>