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Creators/Authors contains: "Vanga, Mukundam"

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  1. Brightly luminescent, diarylboron decorated, cyclic copper trimers with and without cuprophilic interactions have been synthesized and characterized using multiple techniques including X-ray crystallography. 
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  2. In situchemistry of solid silver pyrazolates with ethylene gas, depending on the pyrazolyl ring substituents, stops at a trinuclear complex or leads to complete structure re-organizations producing dinuclear complexes as evident from PXRD data. 
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  3. 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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  4. Described herein are the synthesis, structure, and photophysics of the iodo-substituted cyclic trinuclear copper( i ) complex, Cu 3 [4-I-3,5-(CF 3 ) 2 Pz] 3 supported by a highly-fluorinated pyrazolate in comparison with its previously reported 4-Br/4-Cl analogues. The crystal structure is stabilised by multiple supramolecular interactions of Cu 3 ⋯I and hydrogen/halogen bonding. The photophysical properties and supramolecular interactions are investigated experimentally/computationally for all three 4-halo complexes vis-à-vis relativistic effects. 
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  5. Fluorophores covalently bound to azacrown ether ionophores can be assembled into sensitive turn-on chemosensors. The size specificity and electron rich nature of the ionophore's binding domain contributes to both selectivity... 
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    Free, publicly-accessible full text available September 6, 2026
  6. A useful ligand involving three pyridyl donor arms and fluorocarbon substituents surrounding the coordination pocket has been assembled and utilized in coinage metal chemistry. This tris(pyridyl)borate serves as an excellent ligand support for the stabilization of ethylene complexes of copper, silver and gold. 
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  7. 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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