Mono‐ and Dicoordinate Germanium(0) as a Four‐Electron Donor. Issue 12 (26th January 2018)

• Record Type: Journal Article
• Authors: Mandal, Debdeep; Dhara, Debabrata; Maiti, Avijit; Klemmer, Lukas; Huch, Volker; Zimmer, Michael; Rzepa, Henry S.; Scheschkewitz, David; Jana, Anukul
• Is Part Of: Chemistry. Volume 24:Issue 12(2018)
• Page Start: 2873
• Page End: 2878
• Publication Date: 2018-01-26
• Subjects: carbonyl ligands -- coordination modes -- donor–acceptor systems -- germanium -- subvalent compounds; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201800071
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: We report the synthesis and isolation of molecular iron germanide motifs in the stoichiometry of Fe3 Ge and Fe2 Ge, which are stabilized by the coordination of N‐heterocyclic carbene (NHC) and carbon monoxide (CO) ligands. NHC i Pr 2 Me 2 ⋅Ge[Fe(CO)4 ][Fe2 (CO)8 ] (NHC i Pr 2 Me 2 =1, 3‐diisopropyl‐4, 5‐dimethylimidazol‐2‐ylidene), a germanium(0) ligand with just one NHC as an auxiliary ligand, assumes a bridging coordination mode between a mononuclear [Fe(CO)4 ] and a dinuclear [(CO)4 FeFe(CO)4 ] unit with rapid exchange between the two binding modes in solution. The electronic structure of this species is analysed by NBO and ELF calculations with DFT methods, as well as the mechanistic details of its fluxional coordination behaviour. Treatment of NHC i Pr 2 Me 2 ⋅Ge[Fe(CO)4 ] [Fe2 (CO)8 ] with the sterically less demanding NHC Me 4 (NHC Me 4 =1, 3, 4, 5‐tetramethylimidazol‐2‐ylidene) leads to a dinuclear iron complex (NHC Me 4 )2 Ge[Fe(CO)4 ]2 that contains a bridging germylone ligand with two stabilizing NHC equivalents. Abstract : The syntheses of Ge 0 compounds with one or two auxiliary NHC ligandI andII have been achieved within the coordination sphere of Fe(CO)4 fragments. These species are rare examples of molecular iron germanide motifs, stabilized by the coordination of NHC and CO ligands.