showing 23 related works from this author
Mixed valence mono- and hetero-metallic grid catenanes
2015
Multicomponent self-assembly was employed to obtain, in the solid state, a series of mixed valence mono- and hetero-metallic grid catenanes, which were characterized by single crystal X-ray diffraction.
Mechanochemical Synthesis, Photophysical Properties, and X-ray Structures of N-Heteroacenes
2016
The described mechanochemical methodology is an example of a proof-of-concept in which solution-based tedious, poor yielding, and difficult syntheses of pyrazaacenes are achieved under solvent-free ball-milling conditions; the method is easy, high yielding, time-efficient, and environmentally benign. The synthesized compounds also include pyrazaacenes (N-heteroacenes) that are octacene analogues containing pyrene building blocks. The compounds were sparingly soluble in common solvents, and column chromatographic purifications could be avoided after the solvent-free syntheses. The UV/Vis absorption spectra of the pyrazaacenes show intense absorption bands in the near-IR region. The single-cr…
Hyper-CEST NMR of metal organic polyhedral cages reveals hidden diastereomers with diverse guest exchange kinetics.
2022
AbstractGuest capture and release are important properties of self-assembling nanostructures. Over time, a significant fraction of guests might engage in short-lived states with different symmetry and stereoselectivity and transit frequently between multiple environments, thereby escaping common spectroscopy techniques. Here, we investigate the cavity of an iron-based metal organic polyhedron (Fe-MOP) using spin-hyperpolarized 129Xe Chemical Exchange Saturation Transfer (hyper-CEST) NMR. We report strong signals unknown from previous studies that persist under different perturbations. On-the-fly delivery of hyperpolarized gas yields CEST signatures that reflect different Xe exchange kinetic…
Capturing Hydrophobic Trifluoroiodomethane in Water into an M 4 L 6 Cage
2016
Synthetically important trifluoroiodomethane (CF3I) was trapped in water by using a metal–organic supramolecular anionic cage. Under ambient conditions, nearly 1:1 encapsulation of the hydrophobic, gaseous CF3I substrate with the cage was observed, and its binding constant was calculated by relative comparison with benzene encapsulation.
Self-assembly of a M4L6 complex with unexpected S4 symmetry
2014
Using 1,4-diaminobenzene and 2-formylpyridine as simple building blocks results in a 1D ligand (rod, L2) to 2D (M4L4 grid, C1) to 3D (S4 symmetrical M4L6, C2) complexes upon sequential addition of Cu(I) and Fe(II) ions. The complex C2 can be seen as the smallest possible pseudo-tetrahedron with S4 symmetry. peerReviewed
Encapsulation of Xenon by a Self-Assembled Fe4L6 Metallosupramolecular Cage
2015
We report (129)Xe NMR experiments showing that a Fe4L6 metallosupramolecular cage can encapsulate xenon in water with a binding constant of 16 M(-1). The observations pave the way for exploiting metallosupramolecular cages as economical means to extract rare gases as well as (129)Xe NMR-based bio-, pH, and temperature sensors. Xe in the Fe4L6 cage has an unusual chemical shift downfield from free Xe in water. The exchange rate between the encapsulated and free Xe was determined to be about 10 Hz, potentially allowing signal amplification via chemical exchange saturation transfer. Computational treatment showed that dynamical effects of Xe motion as well as relativistic effects have signific…
Self-assembly of a M4L6 complex with unexpected S4 symmetry
2014
In a one-pot reaction 1,4-diaminobenzene and 2-formylpyridine, as the reacting subcomponents, self-assemble to a small supramolecular M4L6 pseudo-tetrahedron with unexpected S4 symmetry in the presence of Fe(ii) ions.
Size‐Selective Encapsulation of Hydrophobic Guests by Self‐Assembled M 4 L 6 Cobalt and Nickel Cages
2012
Subtle differences in metal-ligand bond lengths between a series of [M(4)L(6)](4-) tetrahedral cages, where M = Fe(II), Co(II), or Ni(II), were observed to result in substantial differences in affinity for hydrophobic guests in water. Changing the metal ion from iron(II) to cobalt(II) or nickel(II) increases the size of the interior cavity of the cage and allows encapsulation of larger guest molecules. NMR spectroscopy was used to study the recognition properties of the iron(II) and cobalt(II) cages towards small hydrophobic guests in water, and single-crystal X-ray diffraction was used to study the solid-state complexes of the iron(II) and nickel(II) cages.
Solvent-free ball-milling subcomponent synthesis of metallosupramolecular complexes.
2015
Subcomponent self-assembly from components A, B, C, D, and Fe(2+) under solvent-free conditions by self-sorting leads to the construction of three structurally different metallosupramolecular iron(II) complexes. Under carefully selected ball-milling conditions, tetranuclear [Fe4 (AD2 )6 ](4-) 22-component cage 1, dinuclear [Fe2 (BD2 )3 ](2-) 11-component helicate 2, and 5-component mononuclear [Fe(CD3 )](2+) complex 3 were prepared simultaneously in a one-pot reaction from 38 components. Through subcomponent substitution reaction by adding subcomponent B, the [Fe4 (AD2 )6 ](4-) cage converts quantitatively to the [Fe2 (BD2 )3 ](2-) helicate, which, in turn, upon addition of subcomponent C, …
Anion-controlled formation of an aminal-(bis)imine Fe(ii)-complex.
2014
In the presence of triflate as the counter anion, 1,2-diaminobenzene and 2-formylpyridine self-sort with iron(II) to a low-spin [Fe(L1)](OTf)2 complex in which both aminal and imine moieties coexist simultaneously, while under similar conditions the chloride anion leads to a high-spin [Fe(L2)Cl2] complex.
Mechanochemical Synthesis, Photophysical Properties, and X-ray Structures of N-Heteroacenes (Eur. J. Org. Chem. 7/2016)
2016
CCDC 1437950: Experimental Crystal Structure Determination
2016
Related Article: Prasit Kumar Sahoo, Chandan Giri, Tuhin Subhra Haldar, Rakesh Puttreddy, Kari Rissanen and Prasenjit Mal|2016|Eur.J.Inorg.Chem.||1283|doi:10.1002/ejoc.201600005
CCDC 1437951: Experimental Crystal Structure Determination
2016
Related Article: Prasit Kumar Sahoo, Chandan Giri, Tuhin Subhra Haldar, Rakesh Puttreddy, Kari Rissanen and Prasenjit Mal|2016|Eur.J.Inorg.Chem.||1283|doi:10.1002/ejoc.201600005
CCDC 1437948: Experimental Crystal Structure Determination
2016
Related Article: Prasit Kumar Sahoo, Chandan Giri, Tuhin Subhra Haldar, Rakesh Puttreddy, Kari Rissanen and Prasenjit Mal|2016|Eur.J.Inorg.Chem.||1283|doi:10.1002/ejoc.201600005
CCDC 1043159: Experimental Crystal Structure Determination
2015
Related Article: Chandan Giri, Prasit Kumar Sahoo, Rakesh Puttreddy, Kari Rissanen, Prasenjit Mal|2015|Chem.-Eur.J.|21|6390|doi:10.1002/chem.201500734
CCDC 1006931: Experimental Crystal Structure Determination
2014
Related Article: Chandan Giri, Filip Topić, Prasenjit Mal, Kari Rissanen|2014|Dalton Trans.|43|15697|doi:10.1039/C4DT02180K
CCDC 1437949: Experimental Crystal Structure Determination
2016
Related Article: Prasit Kumar Sahoo, Chandan Giri, Tuhin Subhra Haldar, Rakesh Puttreddy, Kari Rissanen and Prasenjit Mal|2016|Eur.J.Inorg.Chem.||1283|doi:10.1002/ejoc.201600005
CCDC 1006930: Experimental Crystal Structure Determination
2014
Related Article: Chandan Giri, Filip Topić, Prasenjit Mal, Kari Rissanen|2014|Dalton Trans.|43|15697|doi:10.1039/C4DT02180K
CCDC 1054511: Experimental Crystal Structure Determination
2015
Related Article: Chandan Giri, Filip Topić, Massimo Cametti, Kari Rissanen|2015|Chemical Science|6|5712|doi:10.1039/C5SC01851J
CCDC 1002402: Experimental Crystal Structure Determination
2014
Related Article: Chandan Giri, Filip Topić, Prasenjit Mal, Kari Rissanen|2014|Dalton Trans.|43|17889|doi:10.1039/C4DT02754J
CCDC 1054510: Experimental Crystal Structure Determination
2015
Related Article: Chandan Giri, Filip Topić, Massimo Cametti, Kari Rissanen|2015|Chemical Science|6|5712|doi:10.1039/C5SC01851J
CCDC 1054512: Experimental Crystal Structure Determination
2015
Related Article: Chandan Giri, Filip Topić, Massimo Cametti, Kari Rissanen|2015|Chemical Science|6|5712|doi:10.1039/C5SC01851J
CCDC 1054509: Experimental Crystal Structure Determination
2015
Related Article: Chandan Giri, Filip Topić, Massimo Cametti, Kari Rissanen|2015|Chemical Science|6|5712|doi:10.1039/C5SC01851J