The first metal complexes of the proton sponge 1,8-bis(N,N,N′,N′-tetramethylguanidino)naphthalene

• Verfasst von: Wild, Ute [VerfasserIn]
• Verfasst von: Hübner, Olaf [VerfasserIn]
• Verfasst von: Maronna, Astrid Christine [VerfasserIn]
• Verfasst von: Enders, Markus [VerfasserIn]
• Verfasst von: Kaifer, Elisabeth [VerfasserIn]
• Verfasst von: Wadepohl, Hubert [VerfasserIn]
• Verfasst von: Himmel, Hans-Jörg [VerfasserIn]
• Titel: The first metal complexes of the proton sponge 1,8-bis(N,N,N′,N′-tetramethylguanidino)naphthalene
• Titelzusatz: syntheses and properties
• Verf.angabe: Ute Wild, Olaf Hübner, Astrid Maronna, Markus Enders, Elisabeth Kaifer, Hubert Wadepohl, and Hans-Jörg Himmel
• Jahr: 2008
• Umfang: 8 S.
• Fussnoten: Die "N" im Ausdruck "N,N,N′,N′-tetramethylguanidino" sind im Titel kursiv dargestellt ; Published online: August 26, 2008 ; Gesehen am 24.11.2022
• Titel Quelle: Enthalten in: European journal of inorganic chemistry
• Ort Quelle: Weinheim : Wiley-VCH, 1998
• Jahr Quelle: 2008
• Band/Heft Quelle: (2008), 28, Seite 4440-4447
• ISSN Quelle: 1099-0682
• DOI: doi:10.1002/ejic.200800677
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Chelates
• Sach-SW: Coordination compounds
• Sach-SW: Guanidine
• Sach-SW: Palladium
• Sach-SW: Platinum
• Sach-SW: Proton sponge
• K10plus-PPN: 1823557503

Abstract

In this work we report on the syntheses and properties of the first transition metal complexes of the proton sponge 1,8-bis(N,N,N′,N′-tetramethylguanidino)naphthalene (btmgn). Of the three complexes [(btmgn)PdCl2], [(btmgn)PtCl2] and [(btmgn)PtCl2(C2H4)], 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)PtCl2(C2H4)]. The molecular structures of [(btmgn)PdCl2] and [(btmgn)PtCl2] 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)PtCl2(C2H4)] eliminates ethylene at elevated temperature to give [(btmgn)PtCl2]. Quantum chemical (DFT) calculations indicate that the ΔG0 value for this reaction is close to zero. Indeed the compound [(btmgbp)PtCl2] btmgbp = 2,2′-bis(N,N,N′,N′-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)