The complex [closo-3,3-（PPh<sub>3</sub>）<sub>2</sub>-3-H-3,1,2-RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]has a rich derivative chemistrythat is currently ...The complex [closo-3,3-（PPh<sub>3</sub>）<sub>2</sub>-3-H-3,1,2-RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]has a rich derivative chemistrythat is currently under active investigation.The resultant compound shows an increasing stabilitythat is often associated with metallocarboranes.This paper deals with the novel and the produc-tion area of carborane complexes of transition metals.The paper indicates that some reactions can easily proceed and the resulting compound hassome new properties and uses.K[18-crown-6][closo-3-Ph<sub>3</sub>P-3-CH<sub>2</sub>Ph-3-Br-3,1,2-RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]can be synthesized by the reaction of K[18-crown-6][（Ph<sub>3</sub>P）<sub>2</sub>RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]withbromo-toluene under the condition of dry benzene.IR and <sup>1</sup>H,<sup>11</sup>B,<sup>31</sup>p nuclear magnetic reso-nance and elemental analysis comfirm the structure for this species with one carborane groupbonded to the central metal.展开更多
Halfsandwich iron dicarbonyl complex [η 5-C5H3（t-Bu）2]Fe（CO）2Cl（1） reacts with 1, 2-dilithium diseleno carborane Li2Se2C2B 10H 10（2） to give a binuclear iron carborane complex [η 5-C5H3（t-Bu）2]2Fe2（CO）3&...Halfsandwich iron dicarbonyl complex [η 5-C5H3（t-Bu）2]Fe（CO）2Cl（1） reacts with 1, 2-dilithium diseleno carborane Li2Se2C2B 10H 10（2） to give a binuclear iron carborane complex [η 5-C5H3（t-Bu）2]2Fe2（CO）3·Se2C2B 10H 10（3）. The X-ray diffraction analysis of complex 3 reveals that one of the iron atoms is chiral.展开更多
A new compound [CpCo（Se2C2BIoH9）CH2C（O）C4H30] has been synthesized and characterized by elemental analysis, IR spectroscopy, NMR, MS and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic...A new compound [CpCo（Se2C2BIoH9）CH2C（O）C4H30] has been synthesized and characterized by elemental analysis, IR spectroscopy, NMR, MS and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P21/c with a = 10.9481（10）, b = 24.6600（12）, c = 25.7430（14） A, β = 100.863（3）°, C42H57B30Co306Se6＂CH2C12＂0.25H20, Mr = 1722.16, V = 6825.6（8） A3, Dc= 1.676 g/cm3, Z = 1 and F（000） = 3346. The molecular structure shows a 1：1 ratio product of the two reactants of 16e half-sandwich complex CpCo（Se2C2B10H10） and alkyne 1-（2-furyl）-2-propyn-l-one. The hydrogen atom in the B（3） position of CpCo（Se2C2B10HIo） has been activated and migrated to the terminal carbon of 1-（2-furyl）- 2-propyn-l-one to form the B-CH2 unit. The title compound molecules are linked and extended further into a one-dimensional chain through atypical hydrogen bonds.展开更多
This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carbora...This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl radicals.Such hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)pathway.They are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.展开更多
Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a se...Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),C2h C_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@C_(24)B_(12)0H_(72)2−(6),and D_(5d)C_(2)B_(10)@C_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),close-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly close-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete dehydrogenations.Detailed bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or C_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 rule.The infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and C_(2)B_(10)@C_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.展开更多
Though transition metal-catalyzed cage BH methylation has been well documented, catalytic alkylation of cage BH bonds remained elusive because transition metal alkyl complexes are prone to undergo β-H elimination. We...Though transition metal-catalyzed cage BH methylation has been well documented, catalytic alkylation of cage BH bonds remained elusive because transition metal alkyl complexes are prone to undergo β-H elimination. We report herein a highly efficient 8-aminoquinoline-assisted nickel-catalyzed regioselective cage B(3,4,5,6)-H tetra-alkylation of o-carboranes employing unactivated alkyl bromides as alkylating agents in the absence of any oxidants, leading to the preparation of a class of tetra-alkylated o-carboranes with a broad substrate scope in good to very high yields. This method opens new avenues for oxidant-free, direct, efficient, sustainable, and regioselective multiple B–H alkylation of carboranes via base metal catalysis.展开更多
Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The s...Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been synthesized.The m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar method.All of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.展开更多
The steric and electronic properties of A/-heterocyclic carbenes(NHCs)can be modified by the exocyclic substituents at the nitrogen atoms,by 1-3 atoms'replacements of the five-membered imidazolium skeleton and by ...The steric and electronic properties of A/-heterocyclic carbenes(NHCs)can be modified by the exocyclic substituents at the nitrogen atoms,by 1-3 atoms'replacements of the five-membered imidazolium skeleton and by the changes of the backbones.Herein,we report the usage of nido-C_(2)B_(3) carbora ne anions as the backb ones of NHCs.Stirring the mixture of sec on dary amino o-carbora nes(lb-le),triethyl orthoformate and HBF4-Et2O results in the unexpected cage-opening of o-carboranes to afford the n/do-C_(2)B_(9) carbora ne anions supported A/-heterocyclic carbene precursors(4b-4e).Deprotonation of 4b with sodium hexamethyldisilazide at-78℃ affords the/V-heterocyclic carbene ligand,which was used to form an Au(I)NHC complex(5).DFT calculations revealed a high-lying lone pair orbitals of the carbene ligands,predicting their strong o-donating abilities.展开更多
The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH...The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH_(2)-linkage have been prepared and structurally characterized for comparison.Structural analyses of 13-and 14-vertex heteroboranes as well as control experiments suggest that the facile double desilylation of 2 on silica gel can be attributed to the joint actions of several factors involving the high ring-strain of exo five-membered C_(4)Si ring,Lewis acidity of Si atom and Brønsted acidity of silica surface.展开更多
Base metal catalyzed regioselective cage B–H functionalization has been achieved. Under the assistance of a bidentate directing group, Cu-catalyzed [4+2] annulation of carboranyl amides with internal alkynes affords ...Base metal catalyzed regioselective cage B–H functionalization has been achieved. Under the assistance of a bidentate directing group, Cu-catalyzed [4+2] annulation of carboranyl amides with internal alkynes affords unprecedented C,B-substituted carborane-fused-pyridone derivatives, whereas the use of terminal alkynes leads to B–H/C(sp)–H dehydrocoupling products. The isolation and structural identification of a notably stable Cu(Ⅰ) intermediate shed light on the reaction mechanism, which is proposed to involve a Cu(Ⅲ) intermediate.展开更多
Transmetalation of carborane-fused zirconacycles to Cu（II） induces the C-C coupling reaction to form four-membered rings. This serves as a new efficient and general methodology for the generation of a series of carb...Transmetalation of carborane-fused zirconacycles to Cu（II） induces the C-C coupling reaction to form four-membered rings. This serves as a new efficient and general methodology for the generation of a series of carborane-fused cyclobutenes and cyclobutanes. A reaction mechanism involving transmetalation to Cu（II） and reductive elimination is proposed.展开更多
In this study, two fluorinated polyurethanes（FPU） containing carborane groups in the main chains were firstly designed and synthesized via the reaction of hexamethylene diisocyanate trimer（HDI trimer） with fluorin...In this study, two fluorinated polyurethanes（FPU） containing carborane groups in the main chains were firstly designed and synthesized via the reaction of hexamethylene diisocyanate trimer（HDI trimer） with fluorinated polyesters（CFPETs） having hydroxyl-terminated carborane groups at room temperature. The structures of carborane fluorinated polyesters（CFPETs） and polyurethanes（CFPUs） were characterized by gel permeation chromatography（GPC）, Fourier transform infrared（FTIR） spectroscopy and nuclear magnetic resonance（NMR） measurements. The thermal stability, mechanical properties, Shore A hardness, solvent resistance and acid-alkali resistance of the carborane fluorinated polyurethane films were also studied. Thermogravimetric analysis（TGA） tests manifested that the introduction of carborane groups into the main chain of fluorinated polyurethane endowed the obtained fluorinated polyurethane with excellent thermal stability. The thermal decomposition temperature of carborane fluorinated polyurethane（CFPU） increased by 190 °C compared with that of the carborane-free fluorinated polyurethane（FPU）. Even at 800 °C, CFPU showed the char yield of 66.5%, which was higher than that of FPU（34.3%）. The carborane-containing fluorinated polyurethanes also showed excellent chemical resistance and prominent mechanical property even after the cured films being immersed into Jet aircraft oil or 37% HCl for 168 h or at high temperature（700 °C）. It is found that the structural characteristics of carborane group and the compacted structure of CFPU effectively improve the thermal stability, mechanical property, solvent resistance and acid-alkali resistance of the carborane-free fluorinated polyurethane. These excellent properties make CFPU as the useful raw materials to prepare the high temperature resistant coatings or adhesives for automotive engines, engine or fuel tank of aircraft and other equipment working in high-temperature or high concentrations of acid-alkali environments.展开更多
o-Carboryne （1,2-dehydro-o-carborane） is a very useful synthon for the synthesis of a variety of carborane-functionalized molecules. Diels-Alder reaction of o-carboryne with furans gave a series of carborane-fused o...o-Carboryne （1,2-dehydro-o-carborane） is a very useful synthon for the synthesis of a variety of carborane-functionalized molecules. Diels-Alder reaction of o-carboryne with furans gave a series of carborane-fused oxanorbornenes in moderate to high yields using 1-OTf-1,2-C_2B_10H_11 as carboryne precursor. The resultant cycloadducts can undergo hydrogenation, cyclic oxidation, bromination, [4＋2]/[2＋2] cycloaddition and nucleophilic ring opening reaction to afford a variety of highly functionalized carboranes that may find applications as useful basic units in medicine and materials science.展开更多
Carborane bisphenol novolacs （3 and 4） were synthesized in the presence of acid catalyst from carborane bisphenols （5 and 6） and formaldehyde. Further epoxidization of carborane bisphenol novolacs with epichlorohy...Carborane bisphenol novolacs （3 and 4） were synthesized in the presence of acid catalyst from carborane bisphenols （5 and 6） and formaldehyde. Further epoxidization of carborane bisphenol novolacs with epichlorohydrin gave carborane bisphenol epoxy novolacs （1 and 2）. The molecular weight and epoxy value of obtained resins were determined using the molecular weight of their precursors. The epoxy values of 1 and 2 were 0.48 and 0.52 respectively, higher than the maximum theoretical epoxy value （0.45） of difunctional carborane bisphenol epoxy resins. FTIR and NMR were utilized to characterize 1 and 2. The curing behaviors were also studied by DSC and the optimized curing conditions were obtained. TGA analysis indicated that carborane moiety could shield its adjacent organic structures against initial decomposition. On the other hand, B--H on carborane cage could react with oxygen to form a three-dimensional network linked by B--O--B and B--C bonds, which further blocked the movement of formed radicals and thus the degradation process was inhibited.展开更多
o-Carborane-containing poly（hydroxy ethers）（P1, P2 and P3） were synthesized via ＂advancement reaction＂ of o-carborane-containing bisphenol（4） and diglycidyl ether of bisphenols（DGEBA and 1）. FTIR and 1^H^-,...o-Carborane-containing poly（hydroxy ethers）（P1, P2 and P3） were synthesized via ＂advancement reaction＂ of o-carborane-containing bisphenol（4） and diglycidyl ether of bisphenols（DGEBA and 1）. FTIR and 1^H^-, 13^C^-, and 11^ B-NMR were utilized to characterize the obtained polymers. TGA test was conducted under nitrogen and air. It is found that the shielding effect of carborane moiety on its adjacent aromatic structures contributes to high initial decomposition temperatures, while oxygen in air has an adverse effect on the initial decomposition temperature. The oxygen can combine with polymer chain to form peroxide and hydroperoxide groups, which are more reactive during the degradation process. Besides, o-carborane-containing poly（hydroxy ethers） have high char yield at elevated temperatures. The boron atom combines with oxygen from the polymer structure or/and from air, thus to form a three-dimensional network linked with B―O―B and B―C bonds, and retain the polymer weight to a large extent.展开更多
Half-sandwich zirconium complex 3 containing tridentate carborane [S,S,O] ligand 2 [(HOC6H2R2-4,6)(CH2)SC(B10H10) C(Ph)2P=S, R=tBu] was synthesized by the reaction of CpZrCl3(Cp=η5-C5H5) with sodium salt of ligand 2....Half-sandwich zirconium complex 3 containing tridentate carborane [S,S,O] ligand 2 [(HOC6H2R2-4,6)(CH2)SC(B10H10) C(Ph)2P=S, R=tBu] was synthesized by the reaction of CpZrCl3(Cp=η5-C5H5) with sodium salt of ligand 2. Zirconium complex 3 was characterized by elemental and NMR analyses. DFT calculations were also performed on complex 3 to analyze the stereochemistry. The results from DFT calculations indicate that structure S1, in which no sulfur atom bonds to the zirconium atom, exists at the lowest energy level. In the presence of methylaluminoxane(MAO), complex 3 exhibited good catalytic activities for ethylene polymerization and long life-time up to 10 h. Moreover, the complex 3/MAO system displayed excellent catalytic activities toword ethylene copolymerization with 1-hexene or polar olefins.展开更多
The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates （denoted as FcSB1, FcSB2 and FcSBCO） and hemoglobin （Hb） are investigated by electrochemistry, fluorescen...The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates （denoted as FcSB1, FcSB2 and FcSBCO） and hemoglobin （Hb） are investigated by electrochemistry, fluorescence and UVvis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H20/02 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state （oxygenated conformation, relax） to T state （deoxygenated conformation, tense）. The binding affinity is in the order of FcSBCO〉FeSB2〉FeSB1. Moreover, the fluorescence study illustrates that the three ferrocenecarborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the 1337Trp residue which is located on the cql32 interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the proteinbinding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs.展开更多
This article describes comparison of the anchoring effect on electronic properties of the helicene-like bibenzothiophene between o-carborane and 5,6-dicarba-nido-decaborane. The o-carborane and nido-decaborane-fused b...This article describes comparison of the anchoring effect on electronic properties of the helicene-like bibenzothiophene between o-carborane and 5,6-dicarba-nido-decaborane. The o-carborane and nido-decaborane-fused bibenzothiophenes were simultaneously obtained in the same reaction and successfully isolated. Initially, the X-ray single crystal analysis revealed that the helicene-like distorted structure was realized in the nido-decaborane-fused bibenzothiophene. From optical measurements in the solution state, distinct different characteristics depending on the type of anchors were observed. It was summarized that the absorption and luminescent properties originated from weak π-conjugation at the bibenzothiophene moiety in the o-carboranefused compound were obtained, whereas robust π-conjugation and significant emission from the intramolecular charge transfer state were detected from the nido-decaborane-fused compound. These data can be explained by the theoretical results that π-conjugation was restrictedly developed within the bibenzothiophene moiety in frontier orbitals of the o-carborane-fused compound. In contrast, π-conjugation can be constructed even through the distorted bibenzothiophene because of the nido-decaborane unit. Moreover, the intramolecular charge transfer state should be realized because of electronic interaction involving the nido-decaborane unit in the excited state. Furthermore, it was demonstrated that the nido-decaborane-fused compound possessed solid-state emission and mechanochromic luminescent properties. The π-conjugation on the distorted structure supported by the nido-decaborane anchor should play a significant role in suppressing aggregation-caused quenching followed by presenting solid-state emission with stimuli responsiveness.展开更多
We report herein a practical approach for regio-selective B—H/C—H bond activation at azo-substituted carboranes. The reaction proceeded through Iridium(III)-induced selective B—H/C—H bond activations based on an a...We report herein a practical approach for regio-selective B—H/C—H bond activation at azo-substituted carboranes. The reaction proceeded through Iridium(III)-induced selective B—H/C—H bond activations based on an azo directing group. Through this strategy, a series of mononuclear, trinuclear and tetranuclear cyclometalated iridium complexes containing Cp*Ir—B or Cp*Ir—C bonds were successfully isolated in a high yield. In this work, efficient routes are developed through one-pot reactions to prepare polynuclear organometallic complexes.展开更多
Carboranes are a class of polyhedral boron-carbon molecular clusters,they can serve as versatile ligands in stabilizing low-valent main group element compounds,due to their exceptionally thermal and chemical stabiliti...Carboranes are a class of polyhedral boron-carbon molecular clusters,they can serve as versatile ligands in stabilizing low-valent main group element compounds,due to their exceptionally thermal and chemical stabilities,easy modifications at the cage carbon vertices,as well as large spherical steric effects.These carborane-based ligands provide interesting opportunities for the synthesis of low-valent main group element compounds with novel structure and reactivity,which indeed enrich the chemistry of low-valent element main group compounds.This review summarizes the recent advances in the chemistry of lowvalent group 13 and group 14 element compounds supported by carborane-based ligands.Achievements and perspectives in this new and flourishing field are discussed in this review.展开更多
文摘The complex [closo-3,3-（PPh<sub>3</sub>）<sub>2</sub>-3-H-3,1,2-RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]has a rich derivative chemistrythat is currently under active investigation.The resultant compound shows an increasing stabilitythat is often associated with metallocarboranes.This paper deals with the novel and the produc-tion area of carborane complexes of transition metals.The paper indicates that some reactions can easily proceed and the resulting compound hassome new properties and uses.K[18-crown-6][closo-3-Ph<sub>3</sub>P-3-CH<sub>2</sub>Ph-3-Br-3,1,2-RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]can be synthesized by the reaction of K[18-crown-6][（Ph<sub>3</sub>P）<sub>2</sub>RhC<sub>2</sub>B<sub>9</sub>H<sub>11</sub>]withbromo-toluene under the condition of dry benzene.IR and <sup>1</sup>H,<sup>11</sup>B,<sup>31</sup>p nuclear magnetic reso-nance and elemental analysis comfirm the structure for this species with one carborane groupbonded to the central metal.
基金Supported by the National Natural Science Foundation of China( No.2 99740 2 9,2 992 5 10 1) and Special Funds forMajor State Basic Research Projects of China( G19990 64 80 0)
文摘Halfsandwich iron dicarbonyl complex [η 5-C5H3（t-Bu）2]Fe（CO）2Cl（1） reacts with 1, 2-dilithium diseleno carborane Li2Se2C2B 10H 10（2） to give a binuclear iron carborane complex [η 5-C5H3（t-Bu）2]2Fe2（CO）3·Se2C2B 10H 10（3）. The X-ray diffraction analysis of complex 3 reveals that one of the iron atoms is chiral.
基金Project supported by the Science and Technology Research Project of Key Laboratory of Higher Institutions of Jiangxi Province(No.GJJl 1710)the Science and Technology Research Projects of the Education Department of Jiangxi Province(Nos.GJJ09376 and GJJ10613)+2 种基金the National Natural Science Foundation of China(21361022 and 21261020)the Scientific and Technological Landing Project of Higher Education of Jiangxi Province(No.KJLD12094)the Fourth Point of Specialty Construction College of Education Ministry(No.TS11524)
文摘A new compound [CpCo（Se2C2BIoH9）CH2C（O）C4H30] has been synthesized and characterized by elemental analysis, IR spectroscopy, NMR, MS and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P21/c with a = 10.9481（10）, b = 24.6600（12）, c = 25.7430（14） A, β = 100.863（3）°, C42H57B30Co306Se6＂CH2C12＂0.25H20, Mr = 1722.16, V = 6825.6（8） A3, Dc= 1.676 g/cm3, Z = 1 and F（000） = 3346. The molecular structure shows a 1：1 ratio product of the two reactants of 16e half-sandwich complex CpCo（Se2C2B10H10） and alkyne 1-（2-furyl）-2-propyn-l-one. The hydrogen atom in the B（3） position of CpCo（Se2C2B10HIo） has been activated and migrated to the terminal carbon of 1-（2-furyl）- 2-propyn-l-one to form the B-CH2 unit. The title compound molecules are linked and extended further into a one-dimensional chain through atypical hydrogen bonds.
基金supported by a grant from the Southern University of Science and Technology.
文摘This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl radicals.Such hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)pathway.They are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.
基金supported by the National Natural Science Foundation of China(Nos.22373061,21973057,and 22003034).
文摘Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),C2h C_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@C_(24)B_(12)0H_(72)2−(6),and D_(5d)C_(2)B_(10)@C_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),close-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly close-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete dehydrogenations.Detailed bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or C_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 rule.The infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and C_(2)B_(10)@C_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.
基金supported by the Research Grants Council of the Hong Kong Special Administration Region (SRFS20214S05)。
文摘Though transition metal-catalyzed cage BH methylation has been well documented, catalytic alkylation of cage BH bonds remained elusive because transition metal alkyl complexes are prone to undergo β-H elimination. We report herein a highly efficient 8-aminoquinoline-assisted nickel-catalyzed regioselective cage B(3,4,5,6)-H tetra-alkylation of o-carboranes employing unactivated alkyl bromides as alkylating agents in the absence of any oxidants, leading to the preparation of a class of tetra-alkylated o-carboranes with a broad substrate scope in good to very high yields. This method opens new avenues for oxidant-free, direct, efficient, sustainable, and regioselective multiple B–H alkylation of carboranes via base metal catalysis.
基金supported by the National Natural Science Foundation of China (Nos.22031003,21720102004)the Shanghai Science Technology Committee (No.19DZ2270100).
文摘Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane ligand.The substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been synthesized.The m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar method.All of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.
基金support from the National Natural Science Foundation of China(Grant No.21771048)the Natural Science Foundation of Zhejiang Provinee(Grant No.LY17B010002).
文摘The steric and electronic properties of A/-heterocyclic carbenes(NHCs)can be modified by the exocyclic substituents at the nitrogen atoms,by 1-3 atoms'replacements of the five-membered imidazolium skeleton and by the changes of the backbones.Herein,we report the usage of nido-C_(2)B_(3) carbora ne anions as the backb ones of NHCs.Stirring the mixture of sec on dary amino o-carbora nes(lb-le),triethyl orthoformate and HBF4-Et2O results in the unexpected cage-opening of o-carboranes to afford the n/do-C_(2)B_(9) carbora ne anions supported A/-heterocyclic carbene precursors(4b-4e).Deprotonation of 4b with sodium hexamethyldisilazide at-78℃ affords the/V-heterocyclic carbene ligand,which was used to form an Au(I)NHC complex(5).DFT calculations revealed a high-lying lone pair orbitals of the carbene ligands,predicting their strong o-donating abilities.
基金The work described in this paper was supported by grants from the Research Grants Council of the Hong Kong Special Administration Region(Nos.404610 and CUHK7/CRF/12G).
文摘The reasons for facile double desilylation of 13-vertex carborane 1,2-Me_(2)Si(CH_(2))_(2)-1,2-C_(2)B_(11)H_(11)(2)are discussed in this article.New 13-and 14-vertex ruthenacarboranes bearing the same-CH_(2)SiMe_(2)CH_(2)-linkage have been prepared and structurally characterized for comparison.Structural analyses of 13-and 14-vertex heteroboranes as well as control experiments suggest that the facile double desilylation of 2 on silica gel can be attributed to the joint actions of several factors involving the high ring-strain of exo five-membered C_(4)Si ring,Lewis acidity of Si atom and Brønsted acidity of silica surface.
基金supported by the Research Grants Council of The Hong Kong Special Administration Region(14304115,14305017)CUHK Direct Grant and Incentive Grant from Faculty of Science,CUHK
文摘Base metal catalyzed regioselective cage B–H functionalization has been achieved. Under the assistance of a bidentate directing group, Cu-catalyzed [4+2] annulation of carboranyl amides with internal alkynes affords unprecedented C,B-substituted carborane-fused-pyridone derivatives, whereas the use of terminal alkynes leads to B–H/C(sp)–H dehydrocoupling products. The isolation and structural identification of a notably stable Cu(Ⅰ) intermediate shed light on the reaction mechanism, which is proposed to involve a Cu(Ⅲ) intermediate.
基金supported by the Research Grants Council of the Hong Kong Special Administration Region (404011)the National Natural Science Foundation of China (21372245 to QIU ZaoZao)
文摘Transmetalation of carborane-fused zirconacycles to Cu（II） induces the C-C coupling reaction to form four-membered rings. This serves as a new efficient and general methodology for the generation of a series of carborane-fused cyclobutenes and cyclobutanes. A reaction mechanism involving transmetalation to Cu（II） and reductive elimination is proposed.
基金financially supported by International Cooperative Project (Harbin Institute of Technology 2014DFR40370)International Cooperative Project (Wuxi HIT Limited Corporation & Research Institute of New Materials BZ2015024)
文摘In this study, two fluorinated polyurethanes（FPU） containing carborane groups in the main chains were firstly designed and synthesized via the reaction of hexamethylene diisocyanate trimer（HDI trimer） with fluorinated polyesters（CFPETs） having hydroxyl-terminated carborane groups at room temperature. The structures of carborane fluorinated polyesters（CFPETs） and polyurethanes（CFPUs） were characterized by gel permeation chromatography（GPC）, Fourier transform infrared（FTIR） spectroscopy and nuclear magnetic resonance（NMR） measurements. The thermal stability, mechanical properties, Shore A hardness, solvent resistance and acid-alkali resistance of the carborane fluorinated polyurethane films were also studied. Thermogravimetric analysis（TGA） tests manifested that the introduction of carborane groups into the main chain of fluorinated polyurethane endowed the obtained fluorinated polyurethane with excellent thermal stability. The thermal decomposition temperature of carborane fluorinated polyurethane（CFPU） increased by 190 °C compared with that of the carborane-free fluorinated polyurethane（FPU）. Even at 800 °C, CFPU showed the char yield of 66.5%, which was higher than that of FPU（34.3%）. The carborane-containing fluorinated polyurethanes also showed excellent chemical resistance and prominent mechanical property even after the cured films being immersed into Jet aircraft oil or 37% HCl for 168 h or at high temperature（700 °C）. It is found that the structural characteristics of carborane group and the compacted structure of CFPU effectively improve the thermal stability, mechanical property, solvent resistance and acid-alkali resistance of the carborane-free fluorinated polyurethane. These excellent properties make CFPU as the useful raw materials to prepare the high temperature resistant coatings or adhesives for automotive engines, engine or fuel tank of aircraft and other equipment working in high-temperature or high concentrations of acid-alkali environments.
文摘o-Carboryne （1,2-dehydro-o-carborane） is a very useful synthon for the synthesis of a variety of carborane-functionalized molecules. Diels-Alder reaction of o-carboryne with furans gave a series of carborane-fused oxanorbornenes in moderate to high yields using 1-OTf-1,2-C_2B_10H_11 as carboryne precursor. The resultant cycloadducts can undergo hydrogenation, cyclic oxidation, bromination, [4＋2]/[2＋2] cycloaddition and nucleophilic ring opening reaction to afford a variety of highly functionalized carboranes that may find applications as useful basic units in medicine and materials science.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.JD-1512)
文摘Carborane bisphenol novolacs （3 and 4） were synthesized in the presence of acid catalyst from carborane bisphenols （5 and 6） and formaldehyde. Further epoxidization of carborane bisphenol novolacs with epichlorohydrin gave carborane bisphenol epoxy novolacs （1 and 2）. The molecular weight and epoxy value of obtained resins were determined using the molecular weight of their precursors. The epoxy values of 1 and 2 were 0.48 and 0.52 respectively, higher than the maximum theoretical epoxy value （0.45） of difunctional carborane bisphenol epoxy resins. FTIR and NMR were utilized to characterize 1 and 2. The curing behaviors were also studied by DSC and the optimized curing conditions were obtained. TGA analysis indicated that carborane moiety could shield its adjacent organic structures against initial decomposition. On the other hand, B--H on carborane cage could react with oxygen to form a three-dimensional network linked by B--O--B and B--C bonds, which further blocked the movement of formed radicals and thus the degradation process was inhibited.
基金financially supported by National Key R&D Program of China(No.2016YFB0302105)
文摘o-Carborane-containing poly（hydroxy ethers）（P1, P2 and P3） were synthesized via ＂advancement reaction＂ of o-carborane-containing bisphenol（4） and diglycidyl ether of bisphenols（DGEBA and 1）. FTIR and 1^H^-, 13^C^-, and 11^ B-NMR were utilized to characterize the obtained polymers. TGA test was conducted under nitrogen and air. It is found that the shielding effect of carborane moiety on its adjacent aromatic structures contributes to high initial decomposition temperatures, while oxygen in air has an adverse effect on the initial decomposition temperature. The oxygen can combine with polymer chain to form peroxide and hydroperoxide groups, which are more reactive during the degradation process. Besides, o-carborane-containing poly（hydroxy ethers） have high char yield at elevated temperatures. The boron atom combines with oxygen from the polymer structure or/and from air, thus to form a three-dimensional network linked with B―O―B and B―C bonds, and retain the polymer weight to a large extent.
基金supported by the National Natural Science Foundation of China (91122017, 21374019)the Shanghai Science and Technology Committee (13JC1400600, 13DZ2275200)the Program for Changjiang Scholars and Innovative Research Team in University (IRT1117)
文摘Half-sandwich zirconium complex 3 containing tridentate carborane [S,S,O] ligand 2 [(HOC6H2R2-4,6)(CH2)SC(B10H10) C(Ph)2P=S, R=tBu] was synthesized by the reaction of CpZrCl3(Cp=η5-C5H5) with sodium salt of ligand 2. Zirconium complex 3 was characterized by elemental and NMR analyses. DFT calculations were also performed on complex 3 to analyze the stereochemistry. The results from DFT calculations indicate that structure S1, in which no sulfur atom bonds to the zirconium atom, exists at the lowest energy level. In the presence of methylaluminoxane(MAO), complex 3 exhibited good catalytic activities for ethylene polymerization and long life-time up to 10 h. Moreover, the complex 3/MAO system displayed excellent catalytic activities toword ethylene copolymerization with 1-hexene or polar olefins.
基金supported by the National Basic Research Program of China (2010CB732404, 2010CB923303)the National Natural Science Foundation of China (21175020, 90713023, 20925104)+4 种基金the Project of High Technology Research and Development Program of China (2007AA022007)Gongdong Province (2011B090400357)the Natural Science Foundation of Jiangsu Province (BK2008149, BK2010052)C. W. acknowledges the Fundamental Research Funds for the Central Universities (ZYGX2011J099)the support by the Open Research Fund of State Key Laboratory of Bioelectronics, Southeast University (2011E09)
文摘The interactions between the new organometallic complexes, ferrocenesubstituted dithioocarborane conjugates （denoted as FcSB1, FcSB2 and FcSBCO） and hemoglobin （Hb） are investigated by electrochemistry, fluorescence and UVvis absorption spectroscopy. The results demonstrate that FcSB1, FcSB2 and FcSBCO can bind to the heme iron center through the replacement of the weakly bound H20/02 in the distal heme pocket of Hb by their sulfur donor atoms, inducing the allosteric change from the R state （oxygenated conformation, relax） to T state （deoxygenated conformation, tense）. The binding affinity is in the order of FcSBCO〉FeSB2〉FeSB1. Moreover, the fluorescence study illustrates that the three ferrocenecarborane conjugates differently affect the quarterly and tertiary structures as well as the polarity in the surrounding of the Trp and Tyr residues in Hb. Typically, FcSB2 mainly induces alterations of the microenvironment around the 1337Trp residue which is located on the cql32 interface of Hb. Such distinct influences are attributed to the structural features of FcSB1, FcSB2 and FcSBCO containing hydrophobic ferrocenyl and carboranyl units as well as C=O group. Screening the proteinbinding behavior can signify the potential bioactivity of such molecules and may be helpful in the future development of promising multifunctional metallodrugs.
基金supported by Konica Minolta Science and Technology Foundation (for K.T.)a Grant-in-Aid for Scientific Research on Innovative Areas "New Polymeric Materials Based on Element-Blocks (No.2401)" (JP24102013)
文摘This article describes comparison of the anchoring effect on electronic properties of the helicene-like bibenzothiophene between o-carborane and 5,6-dicarba-nido-decaborane. The o-carborane and nido-decaborane-fused bibenzothiophenes were simultaneously obtained in the same reaction and successfully isolated. Initially, the X-ray single crystal analysis revealed that the helicene-like distorted structure was realized in the nido-decaborane-fused bibenzothiophene. From optical measurements in the solution state, distinct different characteristics depending on the type of anchors were observed. It was summarized that the absorption and luminescent properties originated from weak π-conjugation at the bibenzothiophene moiety in the o-carboranefused compound were obtained, whereas robust π-conjugation and significant emission from the intramolecular charge transfer state were detected from the nido-decaborane-fused compound. These data can be explained by the theoretical results that π-conjugation was restrictedly developed within the bibenzothiophene moiety in frontier orbitals of the o-carborane-fused compound. In contrast, π-conjugation can be constructed even through the distorted bibenzothiophene because of the nido-decaborane unit. Moreover, the intramolecular charge transfer state should be realized because of electronic interaction involving the nido-decaborane unit in the excited state. Furthermore, it was demonstrated that the nido-decaborane-fused compound possessed solid-state emission and mechanochromic luminescent properties. The π-conjugation on the distorted structure supported by the nido-decaborane anchor should play a significant role in suppressing aggregation-caused quenching followed by presenting solid-state emission with stimuli responsiveness.
基金This work was supported by the National Natural Science Foun-dation of China(Nos.21531002,21720102004,22031003)the Shanghai Science Technology Committee(No.13JC1400600).
文摘We report herein a practical approach for regio-selective B—H/C—H bond activation at azo-substituted carboranes. The reaction proceeded through Iridium(III)-induced selective B—H/C—H bond activations based on an azo directing group. Through this strategy, a series of mononuclear, trinuclear and tetranuclear cyclometalated iridium complexes containing Cp*Ir—B or Cp*Ir—C bonds were successfully isolated in a high yield. In this work, efficient routes are developed through one-pot reactions to prepare polynuclear organometallic complexes.
基金the National Natural Science Foundation of China(No.21901039)the Natural Science Foundation of Jiangsu Province(No.BK20190327)。
文摘Carboranes are a class of polyhedral boron-carbon molecular clusters,they can serve as versatile ligands in stabilizing low-valent main group element compounds,due to their exceptionally thermal and chemical stabilities,easy modifications at the cage carbon vertices,as well as large spherical steric effects.These carborane-based ligands provide interesting opportunities for the synthesis of low-valent main group element compounds with novel structure and reactivity,which indeed enrich the chemistry of low-valent element main group compounds.This review summarizes the recent advances in the chemistry of lowvalent group 13 and group 14 element compounds supported by carborane-based ligands.Achievements and perspectives in this new and flourishing field are discussed in this review.
