NMR‐Spectroscopic Detection of an Elusive Protonated and Coinage Metalated Silicide [NHCDippCu(η4‐Si9)H]2− in Solution. Issue 36 (5th July 2021)

• Record Type: Journal Article
• Authors: Streitferdt, Verena; Tiefenthaler, Susanne M.; Shenderovich, Ilya G.; Gärtner, Stefanie; Korber, Nikolaus; Gschwind, Ruth M.
• Is Part Of: European journal of inorganic chemistry. Issue 36(2021)
• Page Start: 3684
• Page End: 3690
• Publication Date: 2021-07-05
• Subjects: Carbene ligands -- Copper -- Liquid ammonia -- Silicides -- Structure elucidation -- Zintl phases; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.202100419
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: A simultaneously protonated and functionalized silicide cluster [NHC Dipp Cu(η 4 ‐Si9 )H] 2− was detected and characterized in liquid ammonia by NMR spectroscopy. Key NMR results were corroborated by theoretical calculations. 1 H‐NMR line‐widths at variable temperatures revealed that proton hopping in the metalated complex [NHC Dipp Cu(η 4 ‐Si9 )H] 2− is less pronounced than in the non‐complexed silicide [HSi9 ] 3− . Besides [HSi9 ] 3− and [NHC Dipp Cu(η 4 ‐Si9 )H] 2− also the unprotonated analogous cluster [NHC Dipp Cu(η 4 ‐Si9 )] 3− was detected in solution. In addition, a new 29 Si‐NMR signal was obtained in the course of 29 Si‐NMR studies that we assigned to [NHC Dipp Cu(η 4 ‐Si9 )] 3− . The isolation of crystals of (K[2.2.2]‐crypt)2 K0.48 Rb3.52 [NHC Dipp Cu(η 4 ‐Si9 )]2 prove the availability of the non‐protonated NHC Dipp Cu(η 4 ‐Si9 ) fragment in solution. To the best of our knowledge the detection of [NHC Dipp Cu(η 4 ‐Si9 )H] 2− represents the first case of a protonated and coinage metalated group 14 Zintl cluster in solution so far. Abstract : The protonated, coinage metalated silicide [NHC Dipp Cu(η 4 ‐Si9 )H] 2− was detected and characterized in liquid ammonia by NMR spectroscopy, and the results were corroborated by theoretical calculations. For [NHC Dipp Cu(η 4 ‐Si9 )H] 2− a reduced proton hopping was identified compared to [HSi9 ] 3− . A new 29 Si‐NMR signal was detected and assigned to the unprotonated cluster [NHC Dipp Cu(η 4 ‐Si9 )] 3− . Crystals of the latter were obtained as (K[2.2.2]‐crypt)2 K0.48 Rb3.52 [NHC Dipp Cu(η 4 ‐Si9 )]2 .