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Abstract Sterically loaded, anionic pyridine has been synthesized and utilized successfully in the stabilization of a isoleptic series of coinage metal complexes. The treatment of [4‐(Ph3B)‐2,6‐Trip2Py]K (Trip=2,4,6‐iPr3C6H2) with CuBr(PPh3), AgCl(PPh3) or AuCl(PPh3) (Py=pyridine) afforded the corresponding [4‐(Ph3B)‐2,6‐Trip2Py]M(PPh3) (M=Au, Ag, Cu) complexes, via salt metathesis, as isolable, crystalline solids. Notably, these reactions avoid the facile single electron transfer chemistry reported with the less bulky ligand systems. The X‐ray structures revealed that they are two‐coordinate metal adducts. The M−N and M−P bond distances are longest in the silver and shortest in the copper adduct among the three group 11 family members. Computational analysis revealed an interesting stability dependence on steric bulk of the anionic pyridine (i. e., pyridyl borate) ligand. A comparison of structures and bonding of [4‐(Ph3B)‐2,6‐Trip2Py]Au(PPh3) to pyridine andm‐terphenyl complexes, {[2,6‐Trip2Py]Au(PPh3)}[SbF6] and [2,6‐Trip2Ph]Au(PPh3) are also provided. The Au(I) isocyanide complex, [4‐(Ph3B)‐2,6‐Trip2Py]Au(CNBut) has been stabilized using the same anionic pyridylborate illustrating that it can support other gold‐ligand moieties as well.
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Classical Gold Carbonyl Complexes in Tetrahedral and Trigonal‐Planar Settings
Abstract A unique four‐coordinate, classical gold(I)‐carbonyl complex with substantial backdonation from gold has been isolated by using a B‐methylated and fluorinated tris(pyridyl)borate chelator. Its lighter silver(I) and copper(I) analogs enabled a study of trends in the coinage‐metal family. The B‐arylated ligand version also afforded a gold–carbon monoxide complex that displays a notably low C−O stretch value, but with trigonal planar geometry at the gold. A computational analysis shows that the AuI−CO bonds of these tris(pyridyl)borate ligand‐supported molecules consist of electrostatic attraction, OC→Au σ‐donation, and very significant Au→CO π‐back‐bonding components. The latter is responsible for the observed C−O stretching frequencies, which are lower than in free CO.
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- Award ID(s):
- 1954456
- PAR ID:
- 10478676
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 30
- Issue:
- 5
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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