Showing papers by "Dillip Kumar Chand published in 2012"
TL;DR: In this article, the authors describe self-assemblies formed by the combination of a variety of palladium(II) components and ligands ranging from bi-to polydentate.
172 citations
TL;DR: The entropically-controlled assembly of 1 resulted in a rare saturated, quadruple-stranded metallo-helicate, in which both the left-handed and right-handed helicates exist in the crystal structure.
Abstract: Complexation of the bridging bidentate ligand N,N′-(pyridine-2,6-diyl)dinicotinamide, L with palladium(II) resulted in a single discrete M2L4 self-assembly, 1, in a quantitative manner. The entropically-controlled assembly of 1 resulted in a rare saturated, quadruple-stranded metallo-helicate, in which both the left-handed (M) and right-handed (P) helicates exist in the crystal structure.
41 citations
TL;DR: In this paper, the self-assembled binuclear coordination cages of general formula [Pd2(N-N)-N 2 (L)2(L) 2]-X)4, 1a, 2b, 3b, 4a, and 4b are characterized by NMR and electrospray ionization mass spectrometry (ESI-MS) techniques, and in some cases the structures are confirmed by single crystal X-ray diffraction.
Abstract: Self-assembled binuclear coordination cages of general formula [Pd2(N–N)2(L)2](X)4, 1a/b–4a/b are prepared by the combination of N,N′-bis(m-pyridyl)urea, L, with a variety of cis-protected palladium(II) components, Pd(N–N)(X)2. The cis-protecting units “N–N” employed for the synthesis of 1–4 are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′-bipyridine (bpy), and 1,10-phenanthroline (phen), respectively. The term “X” stands for nitrate and perchlorate for a and b, respectively. The assemblies are characterized by NMR and electrospray ionization mass spectrometry (ESI-MS) techniques, and in some cases (i.e., 1a, 2b, 3b, 4a, and 4b) the structures are confirmed by single crystal X-ray diffraction. The conformations of bound L in the crystal structures of all the Pd(II) complexes are found to be syn-syn. The influence of the presence and absence of π cloud at the cis-protecting units on the crystal packing has been studied in detail. In the packing of [Pd2(phen)2L2](NO3)4, 4a, one unit of [Pd...
32 citations
TL;DR: An unanticipated anion-water cluster is assembled by one bromide and three highly-ordered "water tetramers" within the cavity of a receptor, providing a perfect C(3) symmetric propeller-shaped bromides-water clusters of [Br(H(2)O)(12)](-).
27 citations
14 Sep 2012
TL;DR: In this article, a mixture of dry chlorine and oxygen over molybdenum metal at 250-350 °C is used to produce molybdyl chloride gas, which is then purified by sublimation.
Abstract: [13637-68-8] MoO2Cl2 (MW 198.84)
InChI = 1S/2ClH.Mo.2O/h2*1H;;;/q;;+2;;/p-2
InChIKey = JCFNAADCQWXIJD-UHFFFAOYSA-L
(used as a catalyst for various oxidation and reduction reactions)
Alternate names: dichlorodioxomolybdenum; molybdenum dichloride dioxide; molybdenum dioxide dichloride; molybdenumdioxodichloride; molybdenum dioxychloride; molybdenum oxychloride; molybdyl chloride.
Physical Data: melting point: 175 °C, relative density 3.31 g cm−3 at 25 °C.
Solubility: no quantitative data available, commonly used solvents are methanol, THF, acetonitrile, toluene, and dichloromethane.
Form Supplied in: yellow flakes.
Preparation and Purification: molybdenum dioxide dichloride is prepared by reaction of MoO2 with dry chlorine. The reaction proceeds at 160 °C. The crude product thus formed is purified by sublimation.2 An alternative preparation is to pass a 1:1 mixture of dry chlorine and oxygen over molybdenum metal at 250–350 °C.3
Handling, Storage and Precaution: the compound should be stored under an inert atmosphere to avoid decomposition. Contact with moisture results in formation of toxic hydrogen chloride gas.
2 citations