Nitrous acid (HONO) plays pivotal roles in various metal‐free as well as metal‐mediated routes relevant to biogeochemistry, atmospheric chemistry, and mammalian physiology. While the metastable nature of HONO hinders the detailed investigations into its reactivity at a transition metal site, this report herein utilizes a heteroditopic copper(II) cryptate [
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A CuIIcoordination polymer,
- Award ID(s):
- 2122108
- PAR ID:
- 10502359
- Publisher / Repository:
- International Union of Crystallography
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 80
- Issue:
- 3
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 330 to 334
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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A Copper(II)‐Nitrite Complex Hydrogen‐Bonded to a Protonated Amine in the Second‐Coordination‐Sphere
Abstract oC ]CuIIfeaturing a proton‐responsive second‐coordination‐sphere located at a suitable distance from a [CuII](ONO) core, thereby enabling isolation of a [CuII](κ 1‐ONO⋅⋅⋅H+) complex (2H ‐NO2 ). A set of complementary analytical studies (UV‐vis,14N/15N FTIR,15N NMR, HRMS, EPR, and CHN) on2H‐NO2 and its15N‐isotopomer (2H‐15NO2 ) reveals the formulation of2H‐NO2 as {[oC H]CuII(κ 1‐ONO)}(ClO4)2. Non‐covalent interaction index (NCI) based on reduced density gradient (RDG) analysis on {[oC H]CuII(κ 1‐ONO)}2+discloses a H‐bonding interaction between the apical 3° ammonium site and the nitrite anion bound to the copper(II) site. The FTIR spectra of [CuII](κ 1‐ONO⋅⋅⋅H+) species (2H‐NO2 ) shows a shift of ammonium NH vibrational feature to a lower wavenumber due to the H‐bonding interaction with nitrite. The reactivity profile of [CuII](κ 1‐ONO⋅⋅⋅H+) species (2H‐NO2 ) towards anaerobic nitration of substituted phenol (2,4‐DTBP) is distinctly different relative to that of the closely related tripodal [CuII]‐nitrite complexes (1‐NO2 /3‐NO2 /4‐NO2 ). -
During the course of exploring crystallization conditions in generating metal–organic frameworks (MOFs) for use in the crystalline sponge method, two discrete metal–organic complexes, namely, aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) bromide, [Zn(C18H12N6)(H2O)]Br2, and aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) chloride, [Zn(C18H12N6)(H2O)]Cl2, were encountered. Structures in the orthorhombic space group
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