Silylated Ge 9 Clusters as New Ligands for Cyclic (Alkyl)amino and Mesoionic Carbene Copper Complexes

Autor: Guy Bertrand, Lorenz J. Schiegerl, Wilhelm Klein, Daniel R. Tolentino, Thomas F. Fässler, Mohand Melaimi
Přispěvatelé: UCSD-CNRS Joint Research Chemistry Laboratory (UMI 3555), University of California [San Diego] (UC San Diego), University of California-University of California-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Inorganic Chemistry
Inorganic Chemistry, American Chemical Society, 2019, 58 (5), pp.3256-3264. ⟨10.1021/acs.inorgchem.8b03338⟩
ISSN: 0020-1669
1520-510X
Popis: The coordination of Ge9 Zintl clusters at (carbene)CuI moieties is explored, and the complexes [(CAAC)Cu]2[η3-Ge9{Si(TMS)3}2] (1), (CAAC)Cu[η3-Ge9{Si(TMS)3}3] (2), and (MIC)Cu[η3-Ge9{Si(TMS)3}3] (3) are compared with their known N-heterocyclic carbene (NHC) derivatives (A and B), where CAAC = cyclic (alkyl)amino carbene, MIC = mesoionic carbene, and TMS = trimethylsilane. In analogy to the NHC derivatives, the synthesis of 1-3 proceeds by single-step reactions of (CAAC)CuCl or (MIC)CuCl with the [Ge9R2]2- and [Ge9R3]- [R = Si(TMS)3] cluster ligands, respectively, and yields complexes of (carbene)CuI (carbene = CAAC, MIC) moieties exhibiting η3-coordination modes of the Ge9 deltahedron to the Cu atom. In 1, [Ge9R2]2- acts as a η3-bridging unit for two (CAAC)CuI moieties, and 2 and 3 feature single (carbene)CuI (CAAC and MIC) fragments η3-connected to [Ge9R3]- units. Analysis of the bond lengths in comparison with known examples shows a bond expansion within the coordinated Ge3 triangular faces for all (carbene)CuIGe9 complexes (carbene = NHC, MIC, CAAC). All compounds are characterized by single-crystal X-ray diffractometry, NMR spectroscopy [1H, 13C{1H}, and 29Si{1H}], electrospray ionization mass spectometry, elemental analysis (C, H, and N), and for the first time also by IR and Raman investigations (for 2 and 3). The new complexes add to the known NHC derivatives and extend the exploration of Ge9 clusters with carbene ligands at CuI atoms.
Databáze: OpenAIRE