Trinuclear {Co<sup>2+</sup>–M<sup>3+</sup>–Co<sup>2+</sup>} complexes catalyze reduction of nitro compounds
作者:Sumit Srivastava、Manvender S. Dagur、Afsar Ali、Rajeev Gupta
DOI:10.1039/c5dt03442f
日期:——
characterization of trinuclear Co2+–Co3+–Co2+} and Co2+–Fe3+–Co2+} complexes with accessible peripheral Co(II) ions. Both trinuclear complexes function as efficientreusable heterogeneous catalysts for the selectivereduction of assorted nitrocompounds to the corresponding amines. The mechanistic investigations suggest the involvement of a Co(II)–Co(I) cycle in the catalysis.
Manganese Complexes of Pyrrole‐ and Indolecarboxamide Ligands: Synthesis, Structure, Electrochemistry, and Applications in Oxidative and Lewis‐Acid‐Assisted Catalysis
作者:Sunil Yadav、Sushil Kumar、Rajeev Gupta
DOI:10.1002/ejic.201500773
日期:2015.11
N4 coordination sphere about the MnIII ion. The MnIII complexes of pyrrolecarboxamide ligands are square pyramidal with a fifth Cl atom, whereas analogous complexes of indolecarboxamide ligands are essentially square planar. Electrochemical studies reveal highly negative MnIII/II and moderately positive MnIV/III redox potentials. In situ generated Mn4+ species of the pyrrolecarboxamide ligands were
Three-Dimensional {Co<sup>3+</sup>–Zn<sup>2+</sup>} and {Co<sup>3+</sup>–Cd<sup>2+</sup>} Networks Originated from Carboxylate-rich Building Blocks: Syntheses, Structures, and Heterogeneous Catalysis
作者:Girijesh Kumar、Rajeev Gupta
DOI:10.1021/ic400536e
日期:2013.10.7
The present work shows the utilization of Co3+ complexes appended with either para- or meta-arylcarboxylic acid groups as the molecular building blocks for the construction of three-dimensional Co3+-Zn2+} and Co3+-Cd2+} heterobimetallic networks. The structural characterizations of these networks show several interesting features including well-defined pores and channels. These networks function as heterogeneous and reusable catalysts for the regio- and stereoselective ring-opening reactions of various epoxides and size-selective cyanation reactions of assorted aldehydes.
A Metalloligand Appended with Thiazole Rings: Heterometallic {Co
<sup>3+</sup>
–Zn
<sup>2+</sup>
} and {Co
<sup>3+</sup>
–Cd
<sup>2+</sup>
} Complexes and Their Heterogeneous Catalytic Applications
作者:Deepak Bansal、Geeta Hundal、Rajeev Gupta
DOI:10.1002/ejic.201403072
日期:2015.2
AbstractThis work describes a Co3+‐based metalloligand containing appended thiazole rings and its reactions with secondary metal ions to produce heterometallic Co3+–Zn2+} and Co3+–Cd2+} complexes. Structural studies show that some of the appended thiazole rings from the metalloligand coordinate to secondary metal ions, whereas the remaining ones act as hydrogen‐bond acceptors to metal‐bound CH3OH or H2O molecules. These heterometallic complexes function as reusable heterogeneous catalysts for the ring‐opening reactions of epoxides as well as cyanation and Knoevenagel condensation reactions of aldehydes. The catalytic results illustrate that the microenvironment remains intact during the catalysis and potentially enhances the substrate interaction with the Lewis acidic secondary metal ions.