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Karlheinz Schwartzen - One of the best experts on this subject based on the ideXlab platform.
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halogen und Pseudohalogen substituierte penta und tetramethylcyclopentadine
Chemische Berichte, 1990Co-Authors: Peter Jutzi, Karlheinz SchwartzenAbstract:Halogen- and Pseudohalogen-Substituted Penta- and Tetramethylcyclopentadienes The alkyl halides 5-bromo-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (2), 5-iodo-1,2,3,4,5-pentamethyl-1,3-cycloentadiene (3), and 5-bromo-1,2,3,4-tetramethyl-1,3-cyclopentadiene (8) are formed in good yields by treatment of pentamethylcyclopentadienyllitium (1) and tetramethylcyclopentadienyllithium (7), respectively, with the corresponding cyanogen halides. Reaction of 1 with cyanogen chloride or cyanogen leads to 5-cyano-1,2,3,4,5-pentamethyl-1.3-cyclopentadiene (4). Treatment of 1 with thiocyanogen yields 5-isothiocyanato-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (5). 5-Chloro-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (6) is obtained fro 1 and a mixture of tetrachloromethane and triphenylphosphane. Analogously, the halides 2 and 3 can be synthesized by the reaction of 1 with a mixture of triphenylphosphane and tetrabromomethane or tetraiodomethane. Treatment of 7 with tetrachloromethane and triphenylphosphane yields a mixture of isomers of chlorotetramethylcyclopentadiene.
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Halogen‐ und Pseudohalogen‐substituierte Penta‐ und Tetramethylcyclopentadine
Chemische Berichte, 1990Co-Authors: Peter Jutzi, Karlheinz SchwartzenAbstract:Halogen- and Pseudohalogen-Substituted Penta- and Tetramethylcyclopentadienes The alkyl halides 5-bromo-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (2), 5-iodo-1,2,3,4,5-pentamethyl-1,3-cycloentadiene (3), and 5-bromo-1,2,3,4-tetramethyl-1,3-cyclopentadiene (8) are formed in good yields by treatment of pentamethylcyclopentadienyllitium (1) and tetramethylcyclopentadienyllithium (7), respectively, with the corresponding cyanogen halides. Reaction of 1 with cyanogen chloride or cyanogen leads to 5-cyano-1,2,3,4,5-pentamethyl-1.3-cyclopentadiene (4). Treatment of 1 with thiocyanogen yields 5-isothiocyanato-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (5). 5-Chloro-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (6) is obtained fro 1 and a mixture of tetrachloromethane and triphenylphosphane. Analogously, the halides 2 and 3 can be synthesized by the reaction of 1 with a mixture of triphenylphosphane and tetrabromomethane or tetraiodomethane. Treatment of 7 with tetrachloromethane and triphenylphosphane yields a mixture of isomers of chlorotetramethylcyclopentadiene.
Peter Jutzi - One of the best experts on this subject based on the ideXlab platform.
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halogen und Pseudohalogen substituierte penta und tetramethylcyclopentadine
Chemische Berichte, 1990Co-Authors: Peter Jutzi, Karlheinz SchwartzenAbstract:Halogen- and Pseudohalogen-Substituted Penta- and Tetramethylcyclopentadienes The alkyl halides 5-bromo-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (2), 5-iodo-1,2,3,4,5-pentamethyl-1,3-cycloentadiene (3), and 5-bromo-1,2,3,4-tetramethyl-1,3-cyclopentadiene (8) are formed in good yields by treatment of pentamethylcyclopentadienyllitium (1) and tetramethylcyclopentadienyllithium (7), respectively, with the corresponding cyanogen halides. Reaction of 1 with cyanogen chloride or cyanogen leads to 5-cyano-1,2,3,4,5-pentamethyl-1.3-cyclopentadiene (4). Treatment of 1 with thiocyanogen yields 5-isothiocyanato-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (5). 5-Chloro-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (6) is obtained fro 1 and a mixture of tetrachloromethane and triphenylphosphane. Analogously, the halides 2 and 3 can be synthesized by the reaction of 1 with a mixture of triphenylphosphane and tetrabromomethane or tetraiodomethane. Treatment of 7 with tetrachloromethane and triphenylphosphane yields a mixture of isomers of chlorotetramethylcyclopentadiene.
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Halogen‐ und Pseudohalogen‐substituierte Penta‐ und Tetramethylcyclopentadine
Chemische Berichte, 1990Co-Authors: Peter Jutzi, Karlheinz SchwartzenAbstract:Halogen- and Pseudohalogen-Substituted Penta- and Tetramethylcyclopentadienes The alkyl halides 5-bromo-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (2), 5-iodo-1,2,3,4,5-pentamethyl-1,3-cycloentadiene (3), and 5-bromo-1,2,3,4-tetramethyl-1,3-cyclopentadiene (8) are formed in good yields by treatment of pentamethylcyclopentadienyllitium (1) and tetramethylcyclopentadienyllithium (7), respectively, with the corresponding cyanogen halides. Reaction of 1 with cyanogen chloride or cyanogen leads to 5-cyano-1,2,3,4,5-pentamethyl-1.3-cyclopentadiene (4). Treatment of 1 with thiocyanogen yields 5-isothiocyanato-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (5). 5-Chloro-1,2,3,4,5-pentamethyl-1,3-cyclopentadiene (6) is obtained fro 1 and a mixture of tetrachloromethane and triphenylphosphane. Analogously, the halides 2 and 3 can be synthesized by the reaction of 1 with a mixture of triphenylphosphane and tetrabromomethane or tetraiodomethane. Treatment of 7 with tetrachloromethane and triphenylphosphane yields a mixture of isomers of chlorotetramethylcyclopentadiene.
Robin G Pritchard - One of the best experts on this subject based on the ideXlab platform.
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a comparison of the solid state structures of a series of phenylseleno halogen and Pseudohalogen compounds phsex x cl cn scn
Polyhedron, 2007Co-Authors: Nicholas A. Barnes, Stephen M Godfrey, Robin G Pritchard, Ruth T. A. Halton, Imrana Mushtaq, Simon Parsons, Mark SadlerAbstract:Abstract Structural and spectroscopic data on the series of compounds “PhSeX”, where X = Cl, CN or SCN, are reported and compared with previously reported data on “PhSeX” systems (X = Br and I). The chloro-compound displays a “square” motif, Ph4Se4Cl4, in the solid state, linked by long Se–Se bonds [2.993(3)–3.035(3) A], and forms a loosely held network of Se4 and Cl4 squares in its extended structure. In contrast, the Pseudohalogen derivatives, PhSeCN and PhSeSCN, consist of essentially monomeric units, which form chains held together by weak Se⋯N interactions in the solid state. These Se⋯N interactions are much shorter in PhSeCN, 3.023(3)–3.065(4) A, than in PhSeSCN, 3.348(4) A. Weaker Se⋯N contacts are also present between the chains. The structure of PhSeSCN described here is the first reported crystallographic study of a selenium thiocyanate compound. Spectroscopic studies suggest that all three compounds exist as monomers in solution. The results reported herein illustrate the subtle differences in the solid-state structures of PhSeX compounds.
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A comparison of the solid-state structures of a series of phenylseleno-halogen and Pseudohalogen compounds, PhSeX (X = Cl, CN, SCN)
Polyhedron, 2007Co-Authors: Nicholas A. Barnes, Stephen M Godfrey, Robin G Pritchard, Ruth T. A. Halton, Imrana Mushtaq, Simon Parsons, Mark SadlerAbstract:Abstract Structural and spectroscopic data on the series of compounds “PhSeX”, where X = Cl, CN or SCN, are reported and compared with previously reported data on “PhSeX” systems (X = Br and I). The chloro-compound displays a “square” motif, Ph4Se4Cl4, in the solid state, linked by long Se–Se bonds [2.993(3)–3.035(3) A], and forms a loosely held network of Se4 and Cl4 squares in its extended structure. In contrast, the Pseudohalogen derivatives, PhSeCN and PhSeSCN, consist of essentially monomeric units, which form chains held together by weak Se⋯N interactions in the solid state. These Se⋯N interactions are much shorter in PhSeCN, 3.023(3)–3.065(4) A, than in PhSeSCN, 3.348(4) A. Weaker Se⋯N contacts are also present between the chains. The structure of PhSeSCN described here is the first reported crystallographic study of a selenium thiocyanate compound. Spectroscopic studies suggest that all three compounds exist as monomers in solution. The results reported herein illustrate the subtle differences in the solid-state structures of PhSeX compounds.
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The Reaction of Organo-Selenium and -Tellurium Compounds with Dihalogens, Interhalogens, and Pseudohalogens
Phosphorus Sulfur and Silicon and The Related Elements, 2005Co-Authors: Nicholas A. Barnes, Stephen M Godfrey, Pravat Bhattacharyya, Ruth T. A. Halton, Imrana Mushtaq, Robin G PritchardAbstract:Adducts of selenium and tellurium donor molecules with dihalogens, interhalogens, and Pseudohalogens exhibit a remarkable structural diversity. Some interesting examples of these materials and key factors influencing their formation, structures, and bonding are discussed.
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the structural characterisation of ph3pse ph i the first charge transfer ct complex of a tertiary phosphine containing a Pseudohalogen
Chemical Communications, 1999Co-Authors: Philip D Boyle, Stephen M Godfrey, Charles A Mcauliffe, Robin G Pritchard, Joanne M SheffieldAbstract:The reaction of 2 mol equivalents of triphenylphosphine with diphenyldiselenyldiiodine (Ph2Se2I2) produces the charge transfer (CT) complex Ph3PSe(Ph)I in quantitative yield; this compound represents the first report of a CT complex of a tertiary phosphine that contains a Pseudohalogen.
Anton L. German - One of the best experts on this subject based on the ideXlab platform.
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Pseudohalogens in atom transfer radical polymerization of methyl methacrylate
Journal of Applied Polymer Science, 2007Co-Authors: Nikhil K. Singha, Anton L. GermanAbstract:In recent advances in controlled radical polymerization, atom transfer radical polymerization (ATRP) has achieved increasing interest. This investigation reports the ATRP of methyl methacrylate (MMA) using Pseudohalogens as initiator as well as an anion for copper catalyst. The results were compared with the conventional halide system. Different pseudohalides were used as the initiator for the ATRP of MMA in combination with CuX (X = pseudohalide or halide) as the catalyst. Pseudohalide initiator in combination with Cu(halide) catalyst leads to inefficient ATRP due to slow initiation. Pseudohalide initiator in combination with Cu(pseudohalide) catalyst leads to uncontrolled or no polymerization. The polymers were characterized by using GPC, IR, MALDI-TOF-MS, and TGA analysis. IR and MALDI analysis showed that the resultant polymer had pseudohalide as the end group. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3857–3864, 2007
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atom transfer radical polymerization of styrene using a copper catalyst with a Pseudohalogen anion
Journal of Applied Polymer Science, 2005Co-Authors: Nikhil K. Singha, Anton L. GermanAbstract:Atom transfer radical polymerization has been a very useful method in the recent advances in controlled radical polymerization. It needs an activated alkyl halide as an initiator and a copper halide as a catalyst. This investigation reports the successful application of copper thiocyanate, a catalyst with a pseudohalide anion, in the presence of different ligands such as N,N,N=,N″,N‴,N‴-hexamethyltriethylenetetramine (HMTETA), pentyl-2-pyridylmethaneimine, and substituted bipyridine in the atom transfer radical polymerization of styrene. Among the three ligands used, HMTETA was found to be very efficient. The polymers were characterized with 13C-NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and gel permeation chromatography analysis. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1418–1426, 2005
Malgorzata Szwak - One of the best experts on this subject based on the ideXlab platform.
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halogen und Pseudohalogen verbindungen des tellurs
2007Co-Authors: Malgorzata SzwakAbstract:Titelblatt und Inhaltsverzeichnis Einleitung Allgemeiner Teil Experimenteller Teil Zusammenfassung Summary Kristallographischer Anhang Literaturverzeichnis
