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Nadezhda B. Tamm Dr. Lev N. Sidorov Prof. Dr. Erhard Kemnitz Prof. Dr. Sergey I. Troyanov Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10486-10492
Perfluoroalkylation of a higher fullerene mixture with CF3I or C2F5I, followed by HPLC separation of CF3 and C2F5 derivatives, resulted in the isolation of several C84(RF)n (n=12, 16) compounds. Single‐crystal X‐ray crystallography with the use of synchrotron radiation allowed structure elucidation of eight C84(RF)n compounds containing six different C84 cages (the number of the C84 isomer is given in parentheses): C84 (23)(C2F5)12 ( I ), C84 (22)(CF3)16 ( II ), C84 (22)(C2F5)12 ( III ), C84 (11)(C2F5)12 ( IV ), C84 (16)(C2F5)12 ( V ), C84 (4)(CF3)12 ( VI with toluene and VII with hexane as solvate molecules), and C84 (18)(C2F5)12 ( VIII ). Whereas some connectivity patterns of C84 isomers (22, 23, 11) had previously been unambiguously confirmed by different methods, derivatives of C84 isomers numbers 4, 16, and 18 have been investigated crystallographically for the first time, thus providing direct proof of the connectivity patterns of rare C84 isomers. General aspects of the addition of RF groups to C84 cages are discussed in terms of the preferred positions in the pentagons under the formation of chains, pairs, and isolated RF groups. 相似文献
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The Unanticipated Dimerization of Ce@C2v(9)‐C82 upon Co‐crystallization with Ni(octaethylporphyrin) and Comparison with Monomeric M@C2v(9)‐C82 (M = La,Sc, and Y) 下载免费PDF全文
Prof. Mitsuaki Suzuki Prof. Michio Yamada Prof. Yutaka Maeda Dr. Satoru Sato Prof. Yuta Takano Prof. Filip Uhlík Prof. Zdenek Slanina Prof. Yongfu Lian Prof. Xing Lu Prof. Shigeru Nagase Prof. Marilyn M. Olmstead Prof. Alan L. Balch Prof. Takeshi Akasaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):18115-18122
We report that Ce@C2v(9)‐C82 forms a centrosymmetric dimer when co‐crystallized with Ni(OEP) (OEP = octaethylporphyrin dianion). The crystal structure of {Ce@C2v(9)‐C82}2?2[Ni(OEP)]?4 C6H6 shows that a new C?C bond with a bond length of 1.605(5) Å connects the two cages. The high spin density of the singly occupied molecular orbital (SOMO) on the cage and the pyramidalization of the cage are factors that favor dimerization. In contrast, the treatment of Ni(OEP) with M@C2v(9)‐C82 (M = La, Sc, and Y) results in crystallization of monomeric endohedral fullerenes. A systematic comparison of the X‐ray structures of M@C2v(9)‐C82 (M = Sc, Y, La, Ce, Gd, Yb, and Sm) reveals that the major metal site in each case is located at an off‐center position adjacent to a hexagonal ring along the C2 axis of the C2v(9)‐C82 cage. DFT calculations at the M06‐2X level revealed that the positions of the metal centers in these metallofullerenes M@C2v(9)‐C82 (M = Sc, Y, and Ce), as determined by single‐crystal X‐ray structure studies, correspond to an energy minimum for each compound. 相似文献
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14‐Vertex Heteroboranes with 14 Skeletal Electron Pairs: An Experimental and Computational Study 下载免费PDF全文
Dr. Alasdair P. M. Robertson Nicholas A. Beattie Dr. Greig Scott Dr. Wing Y. Man John J. Jones Prof. Stuart A. Macgregor Dr. Georgina M. Rosair Prof. Alan J. Welch 《Angewandte Chemie (International ed. in English)》2016,55(30):8706-8710
Three isomers of [(Cp*Ru)2C2B10H12], the first examples of 14‐vertex heteroboranes containing 14‐skeletal electron pairs, have been synthesized by the direct electrophilic insertion of a {Cp*Ru+} fragment into the anion [4‐Cp*‐4,1,6‐RuC2B10H12]?. All three compounds have the same unique polyhedral structure having an approximate Cs symmetry and featuring a four‐atom trapezoidal face. X‐ray diffraction studies could confidently identify only one of the two cage C atoms in each structure. The other C atom position has been established by a combination of i) best fitting of computed and experimental 11B and 1H NMR chemical shifts, and ii) consideration of the lowest computed energy for series of isomers studied by DFT calculations. In all three isomers, one cage C atom occupies a degree‐4 vertex on the short parallel edge of the trapezium. 相似文献
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Pierre-Emmanuel Alexandre Dr. Wen-Shan Zhang Dr. Frank Rominger Dr. Sven M. Elbert Prof. Dr. Rasmus R. Schröder Prof. Dr. Michael Mastalerz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19843-19847
Porous shape-persistent organic cages have become the object of interest in recent years because they are soluble and thus processable from solution. A variety of cages can be achieved by applying dynamic covalent chemistry (DCC), but they are less chemically stable. Here the transformation of a salicylimine cage into a quinoline cage by a twelve-fold Povarov reaction as the key step is described. Besides the chemical stability of the cage over a broad pH regime, it shows a unique absorption and emission depending on acid concentration. Furthermore, thin films for the vapor detection of acids were investigated, showing color switches from pale-yellow to red, and characteristic emission profiles. 相似文献
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Bodo Rke Herbert W. Roesky Isabel Usn Peter Müller 《Angewandte Chemie (International ed. in English)》1998,37(10):1432-1433
No bulky substituents are bonded to the silicon centers of the cagelike title compound 1 , which is readily formed by reaction of methyltrichlorosilane with ammonia and sodium. According to X-ray structure analysis, 1 consists of two Si3N3 rings in the chair conformation that are bridged through the silicon centers by NH groups. The result is a cage in which three bars are missing, as can be seen on the right. 相似文献
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An Open‐Cage Fullerene That Mimics the C60H10 (5,5)‐Carbon Nanotube Endcap to Host Acetylene and Hydrogen Cyanide Molecules 下载免费PDF全文
Dr. Chi‐Shian Chen Dr. Wen‐Yann Yeh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16425-16428
Treatment of the open‐cage fullerene C63H4NO2(Ph)2(Py)(N2C6H4) ( 1 ) with methanol at 150 °C results in an orifice‐enlargement reaction to give C69H8NO(CO2Me)(Ph)(Py)(N2C6H4) ( 2 ). The overall yield from C60 to isolated 2 is 6.1 % (four steps). Compound 2 contains a 24‐membered elliptic orifice that spans 8.45 Å along the major axis and 6.37 Å along the minor axis. The skeleton of 2 resembles the hypothetic C60H10 (5,5)‐carbon nanotube endcap. The cup‐shaped structure of 2 is able to include water, hydrogen cyanide, and acetylene, forming H2O@ 2 , HCN@ 2 , and C2H2@ 2 , respectively. The molecular structures of H2O@ 2 and HCN@ 2 have been determined by X‐ray crystallography. The 1H NMR spectra reveal substantial upfield shifts for the endohedral species, such as δ=?10.30 (for H2O), ?2.74 and ?14.26 (for C2H2), and ?1.22 ppm (for HCN), owing to the strong shielding effects of the fullerene cage. 相似文献
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Jian‐Qiang Wang Dr. Saskia Stegmaier Thomas F. Fässler Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(11):1998-2002
Inorganic pentaprismane : The unusual structure of the anion [Co@Ge10]3?, which was obtained by the reaction of K4Ge9 with [Co(C8H12)(C8H13)] in ethylenediamine, raises questions about chemical bonding in the anion. The Zintl ion cluster has virtual D5h symmetry and is a unique example of a ligand‐free cluster that is not a deltahedron. The delocalized chemical bonding is represented in the picture by one of the bonding orbitals of the anion.
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R*OCH2CH2CH2SO2Ph (R*OH = MenOH, (–)‐menthol, ( 3a ); BorOH, (1S)‐(–)‐borneol, ( 3b )) were found to react with n‐BuLi in n‐pentane/n‐hexane and toluene/n‐hexane under deprotonation yielding LiCH(CH2CH2OR*)SO2Ph (R* = Men, ( 4a ); Bor, ( 4b )) which reacted with n‐Bu3SnCl forming the requisite tri(n‐butyl)tin compounds n‐Bu3SnCH(CH2CH2OR*)SO2Ph (R* = Men, ( 5a ); Bor, ( 5b )) as diastereomeric mixtures. The identities of 5a and 5b were unambiguously proved by 1H, 13C and 119Sn NMR spectroscopic measurements. Solutions of 4a afforded crystals of [{LiCH(CH2CH2OMen)SO2Ph}4] ( 4a′ ) for which the structure was determined by single‐crystal X‐ray crystallography. Complex 4a′ crystallized in a tetrameric structure without any additional solvent molecules. There were found direct Li–C bonds (Li1–C1/Li2–C20 2.231(9)/2.236(9) Å). The tetrahedral donor set of Li is completed by three oxygen atoms. One oxygen atom comes from the OMen substituent via intramolecular coordination and two oxygen atoms come from SO2 groups of neighboured LiCH(CH2CH2OMen)SO2Ph moieties. Thus, a heterocubane structure with a Li4S4 core is built up. 相似文献
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Nadezhda B. Tamm Runnan Guan Shangfeng Yang Erhard Kemnitz Sergey I. Troyanov 《化学:亚洲杂志》2019,14(12):2108-2111
High‐temperature trifluoromethylation of isolated‐pentagon‐rule (IPR) fullerene C92 chlorination products followed by HPLC separation of C92(CF3)n derivatives resulted in the isolation and X‐ray structural characterization of IPR C92(38)(CF3)18 and non‐classical C92(NC)(CF3)22. The formation of C92(38)(CF3)18 as the highest CF3 derivative of the known isomer C92(38) can be expected. The formation of C92(NC)(CF3)22 was interpreted as chlorination‐promoted cage transformation of C92(38) followed by trifluoromethylation of non‐classical C92(NC) chloride. Noticeably, C92(NC)(CF3)22 shows the highest degree of trifluoromethylation among all known CF3 derivatives of fullerenes. The addition patterns of C92(38)(CF3)18 and C92(NC)(CF3)22 are discussed and compared to the chlorination patterns of C92(38)Cln compounds. 相似文献
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Dr. Chi‐Shian Chen Ting‐Shen Kuo Dr. Wen‐Yann Yeh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(26):8773-8776
Reaction of C63NO2(Ph)2(Py) ( 1 ) with o‐phenylenediamine and pyridine produces a mixture of C63H4NO2(Ph)2(Py)(N2C6H4) ( 2 ) and H2O@ 2 . Compound 2 is a new open‐cage fullerene containing a 20‐membered heterocyclic orifice, which has been fully characterized by NMR spectroscopy, high‐resolution mass spectrometry, and X‐ray crystallography. The elliptical orifice of 2 spans 7.45 Å along the major axis and 5.62 Å along the minor axis, which is large enough to trap water and small organic molecules. Thus, heating a mixture of 2 and H2O@ 2 with hydrogen cyanide and formaldehyde in chlorobenzene affords HCN@ 2 and H2CO@ 2 , respectively. The 1H NMR spectroscopy reveals substantial upfield shifts for the endohedral species (δ=?1.30 to ?11.30 ppm), owing to the strong shielding effect of the fullerene cage. 相似文献
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Chlorination‐Promoted Skeletal‐Cage Transformations of C88 Fullerene by C2 Losses and a CC Bond Rotation 下载免费PDF全文
Prof. Dr. Shangfeng Yang Dr. Tao Wei Dr. Kerstin Scheurell Prof. Dr. Erhard Kemnitz Prof. Dr. Sergey I. Troyanov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15138-15141
High‐temperature chlorination of fullerene C88 (isomer 33) with VCl4 gives rise to skeletal transformations affording several nonclassical (NC) fullerene chlorides, C86(NC1)Cl24/26 and C84(NC2)Cl26, with one and two heptagons, respectively, in the carbon cages. The branched skeletal transformation including C2 losses as well as a Stone–Wales rearrangement has been comprehensively characterized by the structure determination of two intermediates and three final chlorination products. Quantum‐chemical calculations demonstrate that the average energy of the C?Cl bond is significantly increased in chlorides of nonclassical fullerenes with a large number of chlorinated sites of pentagon–pentagon adjacency. 相似文献
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To study the structures and reactivities of alkali metallated intermediates of calix[4]arenes, three compounds were isolated: [Li(4)(p-tert-butylcalix[4]arene-4H)(thf)(4)](2).6 THF (1), [Li(2)(p-tert-butylcalix[4]arene-2H)(H(2)O)(mu-H(2)O)(thf)].3 THF (2), and [K(4)(p-tert-butylcalix[4]arene-4H)(thf)(5)](2).THF (3). The structure of 1 is shown to be dependent on the coordinating solvent. Partial hydrolysis of 1 leads to the formation of 2. The potassium compound 3 features a different structure to that of 1, due to a higher coordination number as well as stronger cation-pi-bonding interactions. 相似文献
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Dr. Alexey N. Bilyachenko Dr. Mikhail M. Levitsky Alexey I. Yalymov Prof. Alexander A. Korlyukov Prof. Viktor N. Khrustalev Dr. Anna V. Vologzhanina Lidia S. Shul'pina Dr. Nikolay S. Ikonnikov Dr. Alexander E. Trigub Pavel V. Dorovatovskii Dr. Xavier Bantreil Dr. Frédéric Lamaty Dr. Jérôme Long Prof. Joulia Larionova Dr. Igor E. Golub Prof. Elena S. Shubina Prof. Georgiy B. Shul'pin 《Angewandte Chemie (International ed. in English)》2016,55(49):15360-15363
A series of four unprecedented heterometallic metallagermsesquioxanes were synthesized. Their cage‐like architectures have a unique type of molecular topology consisting of the hexairon oxo {Fe6O19} core surrounded in a triangular manner by three cyclic germoxanolates [PhGe(O)O]5. This structural organization induces antiferromagnetic interactions between the FeIII ions through the oxygen atoms. Evaluated for this first time in catalysis, these compounds showed a high catalytic activity in the oxidation of alkanes and the oxidative formation of benzamides from alcohols. 相似文献
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《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(2):592-599
Tetrameric [{RZn(NHNMe2)}4] (R = Me, Et), the first organometallic zinc hydrazides to be described, have been prepared by alkane elimination from dialkylzinc solutions and N,N‐dimethylhydrazine. They were characterised by 1H and 13C NMR and IR spectroscopy, mass spectrometry, elemental analysis and X‐ray crystallography. The compounds form asymmetric aggregates containing the novel Zn4N8 core; tetrahedra of Zn atoms bear the alkyl groups at Zn, with the triangular faces bridged by NHNMe2 substituents. The NH groups are connected to two Zn atoms, and the NMe2 groups to one. Hydrolysis of the compounds with water gives [(RZn)4(OH)(NHNMe2)3] as products, which also were characterised as described above. Higher yields of these hydroxo clusters were achieved in one‐pot syntheses by reaction of dialkylzinc solutions with mixtures of N,N‐dimethylhydrazine and water. They contain Zn4N6O cages, in which one hydroxide in the tetrameric hydrazides described above replaces one NHNMe2 group. Similar products can be prepared with alkoxy instead of hydroxy groups, in analogous one‐pot syntheses with alcohols. Alcoholysis of [EtZn(NHNMe2)]4 with methanol or ethanol gave zinc trishydrazide monoalkoxides, [(EtZn)4(OR)(NHNMe2)3] (R = Me, Et), which have constitutions analogous to the monohydroxides. The organozinc bishydrazide bisalkoxides [(MeZn)4(NHNMe2)2(OEt)2] and [(EtZn)4(NHNMe2)2(OEt)2] were obtained in one‐pot reactions from dialkylzinc solutions with mixtures of the hydrazine and alcohol, and their crystal structures, confirmed by spectroscopic methods in solution, show an unsymmetrical aggregation with the novel Zn4N4O2 cage structure. 相似文献