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Edward R. T. Tiekink - One of the best experts on this subject based on the ideXlab platform.
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A Survey of Supramolecular Aggregation Based on Main Group Element⋯Selenium Secondary Bonding Interactions—A Survey of the Crystallographic Literature
Crystals, 2020Co-Authors: Edward R. T. TiekinkAbstract:The results of a survey of the crystal structures of Main Group Element compounds (M = tin, lead, arsenic, antimony, bismuth, and tellurium) for intermolecular M⋯Se secondary bonding interactions is presented. The identified M⋯Se interactions in 58 crystals can operate independent of conventional supramolecular synthons and can sustain zero-, one-, two, and, rarely, three-dimensional supramolecular architectures, which are shown to adopt a wide variety of topologies. The most popular architecture found in the crystals stabilized by M⋯Se interactions are one-dimensional chains, found in 50% of the structures, followed by zero-dimensional (38%). In the majority of structures, the metal center forms a single M⋯Se contact; however, examples having up to three M⋯Se contacts are evident. Up to about 25% of lead(II)-/selenium-containing crystals exhibit Pb⋯Se tetrel bonding, a percentage falling off to about 15% in bismuth analogs (that is, pnictogen bonding) and 10% or lower for the other cited Elements.
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a survey of supramolecular aggregation based on Main Group Element selenium secondary bonding interactions a survey of the crystallographic literature
Crystals, 2020Co-Authors: Edward R. T. TiekinkAbstract:The results of a survey of the crystal structures of Main Group Element compounds (M = tin, lead, arsenic, antimony, bismuth, and tellurium) for intermolecular M⋯Se secondary bonding interactions is presented. The identified M⋯Se interactions in 58 crystals can operate independent of conventional supramolecular synthons and can sustain zero-, one-, two, and, rarely, three-dimensional supramolecular architectures, which are shown to adopt a wide variety of topologies. The most popular architecture found in the crystals stabilized by M⋯Se interactions are one-dimensional chains, found in 50% of the structures, followed by zero-dimensional (38%). In the majority of structures, the metal center forms a single M⋯Se contact; however, examples having up to three M⋯Se contacts are evident. Up to about 25% of lead(II)-/selenium-containing crystals exhibit Pb⋯Se tetrel bonding, a percentage falling off to about 15% in bismuth analogs (that is, pnictogen bonding) and 10% or lower for the other cited Elements.
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CHAPTER 4:A New Non-Covalent Bonding Mode in Supramolecular Chemistry: Main Group Element Lone-Pair–π(arene) Interactions
Monographs in Supramolecular Chemistry, 2016Co-Authors: Ignez Caracelli, Ionel Haiduc, Julio Zukerman-schpector, Edward R. T. TiekinkAbstract:The influence on supramolecular aggregation patterns exerted by a new synthon, Main Group Element (M) lone-pair⋯π(arene) interactions, is surveyed based on data mining studies of Main Group Element crystal structures. Zero-, one-, and less commonly, two- and three-dimensional architectures are identified based on M(lp)⋯π(arene) interactions acting in isolation of other obvious intermolecular interactions, e.g. hydrogen bonding. Herein, an overview of the different aggregation patterns sustained by M(lp)⋯π(arene) interactions is given which, in the case of thallium(i), may occur in 13% of its crystal structures. General considerations of the formation propensities of M(lp)⋯π(arene) interactions, theoretical considerations and their role in macromolecular structures are also included.
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chapter 4 a new non covalent bonding mode in supramolecular chemistry Main Group Element lone pair π arene interactions
2016Co-Authors: Ignez Caracelli, Ionel Haiduc, Julio Zukermanschpector, Edward R. T. TiekinkAbstract:The influence on supramolecular aggregation patterns exerted by a new synthon, Main Group Element (M) lone-pair⋯π(arene) interactions, is surveyed based on data mining studies of Main Group Element crystal structures. Zero-, one-, and less commonly, two- and three-dimensional architectures are identified based on M(lp)⋯π(arene) interactions acting in isolation of other obvious intermolecular interactions, e.g. hydrogen bonding. Herein, an overview of the different aggregation patterns sustained by M(lp)⋯π(arene) interactions is given which, in the case of thallium(i), may occur in 13% of its crystal structures. General considerations of the formation propensities of M(lp)⋯π(arene) interactions, theoretical considerations and their role in macromolecular structures are also included.
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Main-Group Medicinal Chemistry Including Li and Bi
Comprehensive Inorganic Chemistry II, 2013Co-Authors: H.-l. Seng, Edward R. T. TiekinkAbstract:Main-Group Element compounds were among the first developed in the modern era as pharmaceutical preparations for the treatment of a wide variety of human ailments; it is now recognized that many of these Elements exist in traditional medicine of many societies, for example, arsenic. The use of Main-Group Element compounds in contemporary medicine continues for the treatment of, for example, depression (Li), stomach ulcers (Bi), cancer (As and Ga), and leishmaniasis (Sb). Not surprisingly, new compounds of these Elements, and other Main-Group Elements, continue to be investigated for their potential use in new therapies. In this chapter, the use of Main-Group Elements as therapeutic agents is outlined and also, where understood, comments on biological targets and mechanisms of action. Further, key advances in new potential applications of Main-Group Element compounds in medicine are evaluated.
Ariane Adolf - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Characterisation of Novel Main Group Element Clusters with Tin‐Phosphorus, Tin‐Arsenic, and Germanium‐Phosphorus Skeletons
European Journal of Inorganic Chemistry, 2004Co-Authors: Donna Nikolova, Carsten Von Hänisch, Ariane AdolfAbstract:The reaction of iPr3SiPLi2 with SnCl2 in the mol ratio 1:1 leads to the formation of [Sn7(PSiiPr3)7] (1). The cluster [Sn8(PSiiPr3)6Cl2] (3) is obtained, if the same reaction is carried out with a slight excess of the metal salt. Similar lithium chloride elimination reactions between SnCl2 and iPr3SiAsLi2 in the mol ratio 1:1 and 2:3, however, yield [Sn7(AsSiiPr3)7] (2) and [Sn4(AsSiiPr3)6Li4(Et2O)2] (4), respectively. The metal salt GeCl2(diox)2 (diox = 1,4-dioxane) reacts with iPr3SiPLi2 to give [Ge6(PSiiPr3)6] (5). Compounds 1−5 were characterised by NMR and IR spectroscopic techniques as well as Elemental analysis. The crystal structures were identified by X-ray diffraction analysis, which confirmed that the heptameric skeletons of 1 and 2 are structurally analogous. The Sn/P cluster 3 contains subvalent tin atoms, while 4 forms a Sn4As6Li4 rhombododecahedron and 5 a slightly distorted hexagonal prism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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synthesis and characterisation of novel Main Group Element clusters with tin phosphorus tin arsenic and germanium phosphorus skeletons
European Journal of Inorganic Chemistry, 2004Co-Authors: Donna Nikolova, Carsten Von Hänisch, Ariane AdolfAbstract:The reaction of iPr3SiPLi2 with SnCl2 in the mol ratio 1:1 leads to the formation of [Sn7(PSiiPr3)7] (1). The cluster [Sn8(PSiiPr3)6Cl2] (3) is obtained, if the same reaction is carried out with a slight excess of the metal salt. Similar lithium chloride elimination reactions between SnCl2 and iPr3SiAsLi2 in the mol ratio 1:1 and 2:3, however, yield [Sn7(AsSiiPr3)7] (2) and [Sn4(AsSiiPr3)6Li4(Et2O)2] (4), respectively. The metal salt GeCl2(diox)2 (diox = 1,4-dioxane) reacts with iPr3SiPLi2 to give [Ge6(PSiiPr3)6] (5). Compounds 1−5 were characterised by NMR and IR spectroscopic techniques as well as Elemental analysis. The crystal structures were identified by X-ray diffraction analysis, which confirmed that the heptameric skeletons of 1 and 2 are structurally analogous. The Sn/P cluster 3 contains subvalent tin atoms, while 4 forms a Sn4As6Li4 rhombododecahedron and 5 a slightly distorted hexagonal prism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Rei Kinjo - One of the best experts on this subject based on the ideXlab platform.
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Formation of Boron-Main-Group Element Bonds by Reactions with a Tricoordinate Organoboron L2PhB: (L = Oxazol-2-ylidene).
Inorganic Chemistry, 2017Co-Authors: Lingbing Kong, Li Yongxin, Rakesh Ganguly, Rei KinjoAbstract:The reactivity of L2PhB: (1; L = oxazol-2-ylidene) as well as its transition-metal (chromium and iron) complexes toward Main-Group substrates have been systematically examined, which led to the construction of B–E (E = C, Ga, Cl, H, F, N) bonds. The combination of 1 and triethylborane smoothly captured carbon dioxide concomitant with the formation of B–C and B–O bonds. The soft basic boron center in 1 readily reacted with soft acidic gallium trichloride (GaCl3) to afford the extremely stable adduct 4 involving a B–Ga dative bond. Electrophilic alkylation of a neutral tricoordinate organoboron was first achieved by the treatment of 1 with dichloromethane and methyl trifluoromethanesulfonate (MeOTf), both of which afforded ionic species featuring an additional B–C bond. Comparatively, redox reactions took place when halides of heavier Elements such as germanium dichloride, dichlorophenylphosphine, and chlorodiphenylbismuth were employed as substrates, from which cationic species 7 bearing a B–Cl bond was ob...
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formation of boron Main Group Element bonds by reactions with a tricoordinate organoboron l2phb l oxazol 2 ylidene
Inorganic Chemistry, 2017Co-Authors: Lingbing Kong, Li Yongxin, Rakesh Ganguly, Rei KinjoAbstract:The reactivity of L2PhB: (1; L = oxazol-2-ylidene) as well as its transition-metal (chromium and iron) complexes toward Main-Group substrates have been systematically examined, which led to the construction of B–E (E = C, Ga, Cl, H, F, N) bonds. The combination of 1 and triethylborane smoothly captured carbon dioxide concomitant with the formation of B–C and B–O bonds. The soft basic boron center in 1 readily reacted with soft acidic gallium trichloride (GaCl3) to afford the extremely stable adduct 4 involving a B–Ga dative bond. Electrophilic alkylation of a neutral tricoordinate organoboron was first achieved by the treatment of 1 with dichloromethane and methyl trifluoromethanesulfonate (MeOTf), both of which afforded ionic species featuring an additional B–C bond. Comparatively, redox reactions took place when halides of heavier Elements such as germanium dichloride, dichlorophenylphosphine, and chlorodiphenylbismuth were employed as substrates, from which cationic species 7 bearing a B–Cl bond was ob...
Frank Breher - One of the best experts on this subject based on the ideXlab platform.
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Stretching bonds in Main Group Element compounds—Borderlines between biradicals and closed-shell species
Coordination Chemistry Reviews, 2007Co-Authors: Frank BreherAbstract:Biradicals are molecules consisting of two unpaired electrons in two nearly degenerate non-bonding molecular orbitals (NBMOs). They play a central role in bond breaking and formation processes and are usually very short-lived species under standard laboratory conditions. By replacing the carbon-based skeletons of archetypal organic biradicals by Main Group Elements, intriguing mimics of otherwise only transient species are isolable, which can then be characterized by generally applied methods for stable molecules. Nonetheless, the price to pay for gaining stability is the reduction of the biradical character, which makes their designation as biradicaloids more appropriate. Recent advances in the syntheses and characterization of Main Group Element biradicaloids as well as their chemical reactivity and theoretical investigations served as topic of this review article.
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stretching bonds in Main Group Element compounds borderlines between biradicals and closed shell species
Coordination Chemistry Reviews, 2007Co-Authors: Frank BreherAbstract:Biradicals are molecules consisting of two unpaired electrons in two nearly degenerate non-bonding molecular orbitals (NBMOs). They play a central role in bond breaking and formation processes and are usually very short-lived species under standard laboratory conditions. By replacing the carbon-based skeletons of archetypal organic biradicals by Main Group Elements, intriguing mimics of otherwise only transient species are isolable, which can then be characterized by generally applied methods for stable molecules. Nonetheless, the price to pay for gaining stability is the reduction of the biradical character, which makes their designation as biradicaloids more appropriate. Recent advances in the syntheses and characterization of Main Group Element biradicaloids as well as their chemical reactivity and theoretical investigations served as topic of this review article.
Donna Nikolova - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Characterisation of Novel Main Group Element Clusters with Tin‐Phosphorus, Tin‐Arsenic, and Germanium‐Phosphorus Skeletons
European Journal of Inorganic Chemistry, 2004Co-Authors: Donna Nikolova, Carsten Von Hänisch, Ariane AdolfAbstract:The reaction of iPr3SiPLi2 with SnCl2 in the mol ratio 1:1 leads to the formation of [Sn7(PSiiPr3)7] (1). The cluster [Sn8(PSiiPr3)6Cl2] (3) is obtained, if the same reaction is carried out with a slight excess of the metal salt. Similar lithium chloride elimination reactions between SnCl2 and iPr3SiAsLi2 in the mol ratio 1:1 and 2:3, however, yield [Sn7(AsSiiPr3)7] (2) and [Sn4(AsSiiPr3)6Li4(Et2O)2] (4), respectively. The metal salt GeCl2(diox)2 (diox = 1,4-dioxane) reacts with iPr3SiPLi2 to give [Ge6(PSiiPr3)6] (5). Compounds 1−5 were characterised by NMR and IR spectroscopic techniques as well as Elemental analysis. The crystal structures were identified by X-ray diffraction analysis, which confirmed that the heptameric skeletons of 1 and 2 are structurally analogous. The Sn/P cluster 3 contains subvalent tin atoms, while 4 forms a Sn4As6Li4 rhombododecahedron and 5 a slightly distorted hexagonal prism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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synthesis and characterisation of novel Main Group Element clusters with tin phosphorus tin arsenic and germanium phosphorus skeletons
European Journal of Inorganic Chemistry, 2004Co-Authors: Donna Nikolova, Carsten Von Hänisch, Ariane AdolfAbstract:The reaction of iPr3SiPLi2 with SnCl2 in the mol ratio 1:1 leads to the formation of [Sn7(PSiiPr3)7] (1). The cluster [Sn8(PSiiPr3)6Cl2] (3) is obtained, if the same reaction is carried out with a slight excess of the metal salt. Similar lithium chloride elimination reactions between SnCl2 and iPr3SiAsLi2 in the mol ratio 1:1 and 2:3, however, yield [Sn7(AsSiiPr3)7] (2) and [Sn4(AsSiiPr3)6Li4(Et2O)2] (4), respectively. The metal salt GeCl2(diox)2 (diox = 1,4-dioxane) reacts with iPr3SiPLi2 to give [Ge6(PSiiPr3)6] (5). Compounds 1−5 were characterised by NMR and IR spectroscopic techniques as well as Elemental analysis. The crystal structures were identified by X-ray diffraction analysis, which confirmed that the heptameric skeletons of 1 and 2 are structurally analogous. The Sn/P cluster 3 contains subvalent tin atoms, while 4 forms a Sn4As6Li4 rhombododecahedron and 5 a slightly distorted hexagonal prism. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
