Five new divalent metal coordination polymers containing either 1,3‐adamantanedicarboxylate (adc) or 1,3‐adamantanediacetate (ada) and pillaring dipyridyl ligands were prepared and structurally characterized by single‐crystal X‐ray diffraction. Using the V‐shaped linker 4,4′‐dipyridylamine (dpa), three new phases were isolated. {[Zn2(ada)2(dpa)2]
We report a molecular switching ensemble whose states may be regulated in synergistic fashion by both protonation and photoirradiation. This allows hierarchical control in both a kinetic and thermodynamic sense. These pseudorotaxane-based molecular devices exploit the so-called Texas-sized molecular box (cyclo[2]-(2,6-di(1H-imidazol-1-yl)pyridine)[2](1,4-dimethylenebenzene); 14+, studied as its tetrakis-PF6−salt) as the wheel component. Anions of azobenzene-4,4′-dicarboxylic acid (2H+•2) or 4,4′-stilbenedicarboxylic acid (2H+•3) serve as the threading rod elements. The various forms of 2 and 3 (neutral, monoprotonated, and diprotonated) interact differently with 14+, as do the photoinduced
- PAR ID:
- 10307664
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 118
- Issue:
- 47
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- Article No. e2112973118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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· 4.5H2O}n (1 ) shows a (4,4) grid topology with embedded octameric water clusters. {[Co(ada)(dpa)(H2O)]· H2O}n (2 ) also manifests a 2D dimensionality, but with an intriguing novel (4)(12)(4.125) looped topology. {[Cd(adc)(H2O)2]· H2O}n (3 ) did not incorporate dpa ligands during self‐assembly, but exhibits an uncommon 3‐connected 83etb network topology. [Co(ada)(ebin)]n (4 ) [ebin = ethanediaminebis(nicotinamide)] possesses a (3,6) triangular net based on {Co2(OCO)2} dimeric units. {[Cd(adc)(ebin)]· 2H2O}n (5 ) also shows dimeric units, although linked into a decorated (4,4) grid topology. Magnetic susceptibility studies of compound4 revealed a decrease inχ mT product upon cooling, ascribed to antiferromagnetic coupling concomitant with single‐ion effects [g = 2.39(2) withD = 40(3) cm–1andJ = –3.55(4) cm–1]. Compounds1 and5 undergo blue‐violet fluorescence upon ultraviolet irradiation; the zinc derivative1 shows potential as a sensor for the solution‐phase detection of nitrobenzene andm ‐nitrophenol. Thermal decomposition behavior of the five new phases is also discussed. -
A Copper(II)‐Nitrite Complex Hydrogen‐Bonded to a Protonated Amine in the Second‐Coordination‐Sphere
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