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The formation of dimer [(μ-Cl)Rh-(κ3(P,Si,Si)PhP(o-C6H4CH2SiiPr2)(o-C6H4CH2SiiPrnPr))]2 (Rh-3) with an n-propyl group on one of the silicon atoms as a minor product was affected by the reaction of [RhCl(COD)]2 with proligand PhP(o-C6H4CH2SiHiPr2)2, L1. The major product of the reaction was monomeric 14-electron Rh(III) complex [ClRh(κ3(P,Si,Si)PhP(o-C6H4CH2SiiPr2)2)] (Rh-1). Computations revealed that the monomer–dimer equilibrium is shifted toward the monomer with four isopropyl substituents on the two Si atoms of the ligand as in Rh-1; conversely, the dimer is favored with only one n-propyl as in Rh-3, and with less bulky alkyl substituents such as in [ClRh(κ3(P,Si,Si)PhP(o-C6H4CH2SiMe2)2]2 (Rh-2). Computations on the mechanism of formation of Rh-3 directly from [RhCl(COD)]2 are in agreement with the experimental findings and it is found to be less energetic than if stemming from Rh-1. Additionally, a Si–O–Si complex, [μ-Cl-Rh{κ3(P,Si,C)PPh(o-C6H4CH2SiiPrO SiiPr2CH-o-C6H4)}]2, Rh-4, is generated from the reaction of Rh-1 with adventitious water as a result of intramolecular C–H activation.
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This content will become publicly available on November 21, 2025
Dynamic covalent and noncovalent assembly of o -nitrosocumene in organic solvents and water
ortho-Nitrosocumene (o-NC) exhibits dynamic N,N bonding, interchanging monomer and E/Z-azodioxide dimer structures, the extent of which depends on the environment. As a solid, o-NC is a Z-dimer; in organic solvent, the monomer is favored; and in water, dimers are favored. A supramolecular assembly of o-NC is observed as a separate species by NMR in water, shown to be a novel nanometer-sized aggregate containing B2000 molecules.
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- Award ID(s):
- 2204046
- PAR ID:
- 10626473
- Publisher / Repository:
- Royal Society of Chemistry (London)
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 60
- Issue:
- 94
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 13899 to 13902
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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