ABX-type hybrid organic-inorganic structures have recently emerged as a new class of meltable materials. Here, by the use of phenylphosphonium derivatives as A cation, we study liquid- and glass-forming behavior of a new family of hybrid structures, (RPhP)[Mn(dca)] (R = Me, Et, Ph; dca = dicyanamide). These new compounds melt at 196-237 °C () and then vitrify upon cooling to room temperature, forming glasses.
View Article and Find Full Text PDFFour novel dicyanamide-containing hybrid organic-inorganic ABX structures are reported, and the thermal behaviour of a series of nine perovskite and non-perovskite [AB(N(CN))] (A = (CH)N, (CH)N, (CH)N; B = Co, Fe, Mn) is analyzed. Structure-property relationships are investigated by varying both A-site organic and B-site transition metal cations. In particular, increasing the size of the A-site cation from (CH)N → (CH)N → (CH)N was observed to result in a decrease in through an increase in Δ .
View Article and Find Full Text PDFSeveral organic-inorganic hybrid materials from the metal-organic framework (MOF) family have been shown to form stable liquids at high temperatures. Quenching then results in the formation of melt-quenched MOF glasses that retain the three-dimensional coordination bonding of the crystalline phase. These hybrid glasses have intriguing properties and could find practical applications, yet the melt-quench phenomenon has so far remained limited to a few MOF structures.
View Article and Find Full Text PDFStoring and transferring electrons for multi-electron reduction processes are considered to be the key steps in various important chemical and biological transformations. In this work, we accomplished multi-electron reduction of a carboxylic acid a hydrosilylation pathway where a redox-active phenalenyl backbone in Co(PLY-O,O)(THF), stores electrons and plays a preponderant role in the entire process. This reduction proceeds by single electron transfer (SET) from the mono-reduced ligand backbone leading to the cleavage of the Si-H bond.
View Article and Find Full Text PDFMain group metal based catalysis has been considered to be a cost-effective alternative way to the transition metal based catalysis, due to the high abundance of main group metals in the Earth's crust. Among the main group metals, aluminum is the most abundant (7-8%) in the Earth's crust, making the development of aluminum based catalysts very attractive. So far, aluminum based compounds have been popularly used as Lewis acids in a variety of organic reactions, but chemical transformation demanding a redox based process has never utilized an Al(III) complex as a catalyst.
View Article and Find Full Text PDFAn efficient route towards a heterogeneous transition metal-free catalytic C-H functionalization using a covalently linked graphene oxide-phenalenyl conjugate is described herein (28 examples, which include a core of some biologically relevant biaryl and hetero-biaryls). It is an environmentally benign, economical and heterogeneous platform, whose catalytic activity can easily be regenerated through a simple washing-drying technique and the catalytic activity can be retained even after 10 cycles.
View Article and Find Full Text PDFDirect C-H arylation of arenes and heteroarenes to biaryls at ambient temperature has been accomplished using a phenalenyl-supported iron(III) catalyst. The present catalyst requires a chemical reductant such as potassium and functions without any light stimulation. C-H arylation of various heteroarenes including pyridine as well as unactivated arene such as benzene delivered good to excellent yield (28 examples, up to 92 %) at room temperature.
View Article and Find Full Text PDFIn this report, a ligand-redox assisted catalytic hydrosilylation has been investigated. A phenalenyl ligand coordinated nickel complex has been utilized as an electron reservoir to develop a base metal-assisted catalyst, which very efficiently hydrosilylates a wide variety of olefin substrates under ambient conditions. A mechanistic investigation revealed that a two-electron reduced phenalenyl based biradical nickel complex plays the key role in such catalysis.
View Article and Find Full Text PDFHerein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical.
View Article and Find Full Text PDFThe bridging nature of in situ generated hydroxide ions and carboxylates (RCOO(-); R = CH3, C2H5, CH2Ph) has been utilized to design a new family of [Cu6] coordination complexes: [Cu6(μ3-OH)2(μ-H2L)2(μ1,1,3-O2CCH3)2(μ1,3-O2CCH3)2(μ-ClO4)2](ClO4)2·H2O (), [Cu6(μ3-OH)2(μ-H2L)2(μ1,1,3-O2CC2H5)4(μ-ClO4)2](ClO4)2·2H2O () and [Cu6(μ3-OH)2(μ-H2L)2(μ1,3-O2CCH2Ph)4(ClO4)2](ClO4)2·2H2O (). Tetracarboxylate bridged {Cu2} core units are trapped between two ligand-bound {Cu2(μ-H2L)(μ-OH)}(2+) subunits forming the [Cu6] complexes. The hexanuclear {Cu6(μ3-OH)2(H2L)2(μ-O2CR)4}(4+) cores having six interconnected Cu(II) ions assume a hitherto unknown dumbbell-shaped topology.
View Article and Find Full Text PDFSelective detection of either mercury (Hg2+) or iodide (I-) ion using fluorescence turn-on or turn-off processes is an important area of research. In spite of intensive research, simultaneous detection of both mercury and iodide using fluorescence turn-off-on processes, high sensitivity and theoretical support concerning the mechanisms are still lacking. In the present work, graphene oxide is functionalized by thymine to realize simultaneous detection of both Hg2+ and I- selectively using fluorescence turn-off-on mechanism.
View Article and Find Full Text PDFFour new end-on pseudohalide-bridged dinuclear copper(II) complexes, [Cu2(L(1))2(N3)2]·DMF (1), [Cu2(L(2))2(N3)2] (2), [Cu2(L(3))2(NCS)2] (3), and [Cu2(L(4))2(N3)2] (4) {where HL(1), HL(2), HL(3), and HL(4) are tridentate N2O donor Schiff bases}, are synthesized and characterized. Complexes 1, 2, and 3 possess π···π stacking interactions, while in addition hydrogen-bonding interactions are present in 1 and 3. However, by contrast, complex 4 contains neither type of interaction.
View Article and Find Full Text PDFAmong different nitro compounds, trinitrophenol (TNP) is the most common constituent to prepare powerful explosives all over the world. A few works on the detection of nitro explosives have already been reported in the past few years; however, selectivity is still in its infant stage. As all the nitroexplosives are highly electron deficient in nature, it is very difficult to separate one from a mixture of different nitro compounds by the usual photoinduced electron transfer (PET) mechanism.
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