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James A Ibers - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of the silver maleonitrilediselenolates and silver maleonitriledithiolates k 2 2 2 cryptand 4 ag4 se2c2 cn 2 4 na 2 2 2 cryptand 4 ag4 s2c2 cn 2 4 0 33mecn nbu4 4 ag4 s2c2 cn 2 4 k 2 2 2 cryptand 3 ag se2c2 cn 2 2 2mecn and na 2 2 2 cryptand 3 ag s2c2 cn 2 2
Inorganic Chemistry, 2001Co-Authors: Craig C Mclauchlan, James A IbersAbstract:Reaction of AgBF(4), KNH(2), K(2)Se, Se, and [2.2.2]-cryptand in acetonitrile yields [K([2.2.2]-cryptand)](4)[Ag(4)(Se(2)C(2)(CN)(2))(4)] (1). In the unit cell of 1 there are four [K([2.2.2]-cryptand)](+) units and a tetrahedral Ag(4) anionic core coordinated in mu(1)-Se, mu(2)-Se fashion by each of four mns ligands (mns = maleonitrilediselenolate, [Se(2)C(2)(CN)(2)](2)(-)). Reaction of AgNO(3), Na(2)(mnt) (mnt = maleonitriledithiolate, [S(2)C(2)(CN)(2)](2)(-)), and [2.2.2]-cryptand in acetonitrile yields [Na([2.2.2]-cryptand)](4)[Ag(4)(mnt)(4)].0.33MeCN (2). The Ag(4) anion of 2 is analogous to that in 1. Reaction of AgNO(3), Na(2)(mnt), and [NBu(4)]Br in acetonitrile yields [NBu(4)](4)[Ag(4)(mnt)(4)] (3). The anion of 3 also comprises an Ag(4) core coordinated by four mnt ligands, but the Ag(4) core is diamond-shaped rather than tetrahedral. Reaction of [K([2.2.2]-cryptand)](3)[Ag(mns)(Se(6))] with KNH(2) and [2.2.2]-cryptand in acetonitrile yields [K([2.2.2]-cryptand)](3)[Ag(mns)(2)].2MeCN (4). The anion of 4 comprises an Ag center coordinated by two mns ligands in a tetrahedral arrangement. Reaction of AgNO(3), 2 equiv of Na(2)(mnt), and [2.2.2]-cryptand in acetonitrile yields [Na([2.2.2]-cryptand)](3)[Ag(mnt)(2)] (5). The anion of 5 is analogous to that of 4. Electronic absorption and infrared spectra of each complex show behavior characteristic of metal-maleonitriledichalcogenates. Crystal data (153 K): 1, P2/n, Z = 2, a = 18.362(2) A, b = 16.500(1) A, c = 19.673(2) A, beta = 94.67(1) degrees, V = 5941(1) A(3); 2, P4, Z = 4, a= 27.039(4) A, c = 15.358(3) A, V = 11229(3) A(3); 3, P2(1)/c, Z = 6, a = 15.689(3) A, b = 51.924(11) A, c = 17.393(4) A, beta = 93.51(1) degrees, V = 14142(5) A(3); 4, P2(1)/c, Z = 4, a = 13.997(1) A, b = 21.866(2) A, c = 28.281(2) A, beta = 97.72(1) degrees, V = 8578(1) A(3); 5, P2/n, Z = 2, a = 11.547(2) A, b = 11.766(2) A, c = 27.774(6) A, beta = 91.85(3) degrees, V = 3772(1) A(3).
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syntheses and characterization of the metal maleonitrilediselenolates k 2 2 2 cryptand 2 m se2c2 cn 2 2 m ni pd pt and ni dmf 5 cl 2 ni se2c2 cn 2 2
Inorganic Chemistry, 2001Co-Authors: Craig C Mclauchlan, Scott D Robowski, James A IbersAbstract:Reaction of KNH2, K2Se, Se, [2.2.2]-cryptand, and a metal source yields the metal bis(maleonitrilediselenolates) [K([2.2.2]-cryptand)]2[M(Se2C2(CN)2)2] (M = Ni, 1; Pd, 2, Pt, 3). These compounds are isostructural and crystallize with four formula units in the monoclinic space group P21/c in cells at T = 153 K with parameters (a (A), b (A), c (A), β (deg), V (A3)) of 12.220(1), 15.860(2), 15.306(1), 107.64(2), 2827(1) for 1; 12.291(1), 15.669(1), 15.548(1), 108.55(1), 2839(1) for 2; and 12.292(3), 15.671(3), 15.569(3), 108.59(3), 2842(1) for 3. The cation of 1 has been substituted to yield [Ni(dmf)5Cl]2[Ni(Se2C2(CN)2)2] (4). [Ni(dmf)5Cl]2[Ni(Se2C2(CN)2)2] (4) crystallizes with one molecule in the triclinic space group P1 in a cell with parameters (T = 153 K) of a = 8.842(2) A, b = 13.161(3) A, c = 13.831(3) A, α = 110.08(3)°, β = 95.23(3)°, γ = 93.72(3)°, V = 1484(1) A3. The electronic absorption and infrared spectra are characteristic of metal maleonitrilediselenolates. Cyclic voltammetry shows that the ...
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facile syntheses and structures of new metal maleonitrilediselenolates k 2 2 2 cryptand 3 ag se2c2 cn 2 se6 k 2 2 2 cryptand 2 ni se2c2 cn 2 2 and ni dppp se2c2 cn 2
Inorganic Chemistry, 2000Co-Authors: Craig C Mclauchlan, James A IbersAbstract:Facile syntheses of [K([2.2.2]-cryptand)]3Ag(Se2C2(CN)2)(Se6)] (1) and [K([2.2.2]-cryptand)]2[Ni(Se2C2(CN)2)2] (2) are achieved through reaction of polyselenides with KNH2, [2.2.2]-cryptand, and AgBF4 or Ni(dppp)Cl2 in acetonitrile. The syntheses of 2 and Ni(dppp)(Se2C2(CN)2) (3) may be achieved by reaction of 1 with NiCl2 or Ni(dppp)Cl2 in dmf. These compounds represent the first easily prepared metal−maleonitrilediselenolate derivatives.
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syntheses and crystal structures of k 2 2 2 cryptand 2 m o m o 2 si ch 3 2 2 gese 2 and k 2 2 2 cryptand 2 sb 2 se 6
Inorganic Chemistry, 1997Co-Authors: Donna M Smith, Changwoo Park, James A IbersAbstract:[K(2.2.2-cryptand)]2[(μ-O){μ-O2Si(CH3)2}2(GeSe)2] (1) forms from the adventitious reaction of silicone grease with the residue (dissolved in CH3CN) from the reduction of GeSe2 by K in NH3(l) in the presence of 2.2.2-cryptand. Reduction of SbSe under similar conditions leads to the isolation of [K(2.2.2-cryptand)]2[Sb2Se6] (2).
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different products from the chemical and electrochemical reduction of hgse2 k 2 2 2 cryptand 2 hgse2 and pph4 2 hg se4 2 en
Inorganic Chemistry, 1997Co-Authors: C W Park, Donna M Smith, Michael A Pell, James A IbersAbstract:[PPh4]2[Hg(Se4)2]·en has been prepared from the electrochemical reduction of “HgSe2”, an intimate mixture of HgSe and Se. [K(2.2.2-cryptand)]2[HgSe2] has been isolated from the reduction of HgSe2 by K in NH3(l) in the presence of 2.2.2-cryptand. 77Se NMR experiments indicate that the difference in product formation is the result of the different reduction methods used.
Craig C Mclauchlan - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of the silver maleonitrilediselenolates and silver maleonitriledithiolates k 2 2 2 cryptand 4 ag4 se2c2 cn 2 4 na 2 2 2 cryptand 4 ag4 s2c2 cn 2 4 0 33mecn nbu4 4 ag4 s2c2 cn 2 4 k 2 2 2 cryptand 3 ag se2c2 cn 2 2 2mecn and na 2 2 2 cryptand 3 ag s2c2 cn 2 2
Inorganic Chemistry, 2001Co-Authors: Craig C Mclauchlan, James A IbersAbstract:Reaction of AgBF(4), KNH(2), K(2)Se, Se, and [2.2.2]-cryptand in acetonitrile yields [K([2.2.2]-cryptand)](4)[Ag(4)(Se(2)C(2)(CN)(2))(4)] (1). In the unit cell of 1 there are four [K([2.2.2]-cryptand)](+) units and a tetrahedral Ag(4) anionic core coordinated in mu(1)-Se, mu(2)-Se fashion by each of four mns ligands (mns = maleonitrilediselenolate, [Se(2)C(2)(CN)(2)](2)(-)). Reaction of AgNO(3), Na(2)(mnt) (mnt = maleonitriledithiolate, [S(2)C(2)(CN)(2)](2)(-)), and [2.2.2]-cryptand in acetonitrile yields [Na([2.2.2]-cryptand)](4)[Ag(4)(mnt)(4)].0.33MeCN (2). The Ag(4) anion of 2 is analogous to that in 1. Reaction of AgNO(3), Na(2)(mnt), and [NBu(4)]Br in acetonitrile yields [NBu(4)](4)[Ag(4)(mnt)(4)] (3). The anion of 3 also comprises an Ag(4) core coordinated by four mnt ligands, but the Ag(4) core is diamond-shaped rather than tetrahedral. Reaction of [K([2.2.2]-cryptand)](3)[Ag(mns)(Se(6))] with KNH(2) and [2.2.2]-cryptand in acetonitrile yields [K([2.2.2]-cryptand)](3)[Ag(mns)(2)].2MeCN (4). The anion of 4 comprises an Ag center coordinated by two mns ligands in a tetrahedral arrangement. Reaction of AgNO(3), 2 equiv of Na(2)(mnt), and [2.2.2]-cryptand in acetonitrile yields [Na([2.2.2]-cryptand)](3)[Ag(mnt)(2)] (5). The anion of 5 is analogous to that of 4. Electronic absorption and infrared spectra of each complex show behavior characteristic of metal-maleonitriledichalcogenates. Crystal data (153 K): 1, P2/n, Z = 2, a = 18.362(2) A, b = 16.500(1) A, c = 19.673(2) A, beta = 94.67(1) degrees, V = 5941(1) A(3); 2, P4, Z = 4, a= 27.039(4) A, c = 15.358(3) A, V = 11229(3) A(3); 3, P2(1)/c, Z = 6, a = 15.689(3) A, b = 51.924(11) A, c = 17.393(4) A, beta = 93.51(1) degrees, V = 14142(5) A(3); 4, P2(1)/c, Z = 4, a = 13.997(1) A, b = 21.866(2) A, c = 28.281(2) A, beta = 97.72(1) degrees, V = 8578(1) A(3); 5, P2/n, Z = 2, a = 11.547(2) A, b = 11.766(2) A, c = 27.774(6) A, beta = 91.85(3) degrees, V = 3772(1) A(3).
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syntheses and characterization of the metal maleonitrilediselenolates k 2 2 2 cryptand 2 m se2c2 cn 2 2 m ni pd pt and ni dmf 5 cl 2 ni se2c2 cn 2 2
Inorganic Chemistry, 2001Co-Authors: Craig C Mclauchlan, Scott D Robowski, James A IbersAbstract:Reaction of KNH2, K2Se, Se, [2.2.2]-cryptand, and a metal source yields the metal bis(maleonitrilediselenolates) [K([2.2.2]-cryptand)]2[M(Se2C2(CN)2)2] (M = Ni, 1; Pd, 2, Pt, 3). These compounds are isostructural and crystallize with four formula units in the monoclinic space group P21/c in cells at T = 153 K with parameters (a (A), b (A), c (A), β (deg), V (A3)) of 12.220(1), 15.860(2), 15.306(1), 107.64(2), 2827(1) for 1; 12.291(1), 15.669(1), 15.548(1), 108.55(1), 2839(1) for 2; and 12.292(3), 15.671(3), 15.569(3), 108.59(3), 2842(1) for 3. The cation of 1 has been substituted to yield [Ni(dmf)5Cl]2[Ni(Se2C2(CN)2)2] (4). [Ni(dmf)5Cl]2[Ni(Se2C2(CN)2)2] (4) crystallizes with one molecule in the triclinic space group P1 in a cell with parameters (T = 153 K) of a = 8.842(2) A, b = 13.161(3) A, c = 13.831(3) A, α = 110.08(3)°, β = 95.23(3)°, γ = 93.72(3)°, V = 1484(1) A3. The electronic absorption and infrared spectra are characteristic of metal maleonitrilediselenolates. Cyclic voltammetry shows that the ...
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facile syntheses and structures of new metal maleonitrilediselenolates k 2 2 2 cryptand 3 ag se2c2 cn 2 se6 k 2 2 2 cryptand 2 ni se2c2 cn 2 2 and ni dppp se2c2 cn 2
Inorganic Chemistry, 2000Co-Authors: Craig C Mclauchlan, James A IbersAbstract:Facile syntheses of [K([2.2.2]-cryptand)]3Ag(Se2C2(CN)2)(Se6)] (1) and [K([2.2.2]-cryptand)]2[Ni(Se2C2(CN)2)2] (2) are achieved through reaction of polyselenides with KNH2, [2.2.2]-cryptand, and AgBF4 or Ni(dppp)Cl2 in acetonitrile. The syntheses of 2 and Ni(dppp)(Se2C2(CN)2) (3) may be achieved by reaction of 1 with NiCl2 or Ni(dppp)Cl2 in dmf. These compounds represent the first easily prepared metal−maleonitrilediselenolate derivatives.
Ken Tanaka - One of the best experts on this subject based on the ideXlab platform.
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synthesis of single and double dibenzohelicenes by rhodium catalyzed intramolecular 2 2 2 and 2 1 2 1 cycloaddition
Chemistry: A European Journal, 2018Co-Authors: Ryota Yamano, Yu Shibata, Ken TanakaAbstract:Dibenzo[7]helicenes were synthesized with up to 99 % ee by rhodium(I)/binap-catalyzed enantioselective intramolecular [2+2+2] cycloaddition of 2-phenylnaphthalene-linked triynes. Additionally, [2+1+2+1] cycloaddition products, that is, twisted anthracenes, were also synthesized by using difluorphos as ligand. Although these compounds are not configurationally stable at elevated temperature, their Scholl reactions afforded configurationally stable double dibenzo[6]helicenes. The thus-obtained dibenzo[7]helicene exhibited good circularly polarized luminescence property and the double dibenzo[6]helicene showed high fluorescence quantum yield.
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Enantioselective Helicene Synthesis by Rhodium-Catalyzed [2+2+2] Cycloadditions
Bulletin of the Chemical Society of Japan, 2015Co-Authors: Ken Tanaka, Yuki Kimura, Koichi MurayamaAbstract:The highly enantioselective synthesis of functionalized helicenes and helicene-like molecules have been achieved via rhodium-catalyzed [2+2+2] cycloaddition reactions. The rhodium-catalyzed enantio...
Donna M Smith - One of the best experts on this subject based on the ideXlab platform.
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syntheses and crystal structures of k 2 2 2 cryptand 2 m o m o 2 si ch 3 2 2 gese 2 and k 2 2 2 cryptand 2 sb 2 se 6
Inorganic Chemistry, 1997Co-Authors: Donna M Smith, Changwoo Park, James A IbersAbstract:[K(2.2.2-cryptand)]2[(μ-O){μ-O2Si(CH3)2}2(GeSe)2] (1) forms from the adventitious reaction of silicone grease with the residue (dissolved in CH3CN) from the reduction of GeSe2 by K in NH3(l) in the presence of 2.2.2-cryptand. Reduction of SbSe under similar conditions leads to the isolation of [K(2.2.2-cryptand)]2[Sb2Se6] (2).
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different products from the chemical and electrochemical reduction of hgse2 k 2 2 2 cryptand 2 hgse2 and pph4 2 hg se4 2 en
Inorganic Chemistry, 1997Co-Authors: C W Park, Donna M Smith, Michael A Pell, James A IbersAbstract:[PPh4]2[Hg(Se4)2]·en has been prepared from the electrochemical reduction of “HgSe2”, an intimate mixture of HgSe and Se. [K(2.2.2-cryptand)]2[HgSe2] has been isolated from the reduction of HgSe2 by K in NH3(l) in the presence of 2.2.2-cryptand. 77Se NMR experiments indicate that the difference in product formation is the result of the different reduction methods used.
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preparation and structures of the 2 2 2 cryptand 1 salts of the sb2se4 2 as2s4 2 as10s3 2 and as4se6 2 anions
Inorganic Chemistry, 1996Co-Authors: Donna M Smith, C W Park, James A IbersAbstract:2.2.2-Cryptand(1+) salts of the [Sb2Se4]2-, [As2S4]2-, [As10S3]2-, and [As4Se6]2- anions have been synthesized from the reduction of binary chalcogenide compounds by K in NH3(l) in the presence of the alkali-metal-encapsulating ligand 2.2.2-cryptand (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane), followed by recrystallization from CH3CN. The [Sb2Se4]2- anion, which has crystallographically imposed symmetry 2, consists of two discrete edge-sharing SbSe3 pyramids with terminal Se atoms cis to each other. The Sb−Set bond distance is 2.443(1) A, whereas the Sb−Seb distance is 2.615(1) A (t = terminal; b = bridge). The Seb−Sb−Set angles range from 104.78(4) to 105.18(5)°, whereas the Seb−Sb−Seb angles are 88.09(4) and 88.99(4)°. The 77Se NMR data for this anion in solution are consistent with its X-ray structure (δ 337 and 124 ppm, 1:1 intensity, −30 °C, CH3CN/CD3CN). Similar to this [Sb2Se4]2- anion, the [As2S4]2- anion consists of two discrete edge-sharing AsS3 pyramidal units. The As−St bond d...
Suning Wang - One of the best experts on this subject based on the ideXlab platform.
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syntheses structures and fluxionality of blue luminescent zinc ii complexes zn 2 2 2 tpa cl2 zn 2 2 2 tpa 2 o2ccf3 2 and zn 2 2 3 tpa 4 o2ccf3 2 tpa tripyridylamine
Inorganic Chemistry, 2000Co-Authors: Wenyu Yang, Hartmut Schmider, Yousheng Zhang, Suning WangAbstract:Three novel Zn(II) complexes containing either 2,2‘,2‘ ‘-tripyridylamine (2,2‘,2‘ ‘-tpa) or 2,2‘,3‘ ‘-tripyridylamine (2,2‘,3‘ ‘-tpa) have been synthesized and structurally characterized. Compound 1, Zn(2,2‘,2‘ ‘-tpa)Cl2, has a tetrahedral geometry while compounds 2, Zn(2,2‘,2‘ ‘-tpa)2(O2CCF3)2, and 3, Zn(2,2‘,3‘ ‘-tpa)4(O2CCF3)2, have an octahedral geometry. The 2,2‘,2‘ ‘-tpa ligand in 1 and 2 functions as a bidentate ligand, chelating to the zinc center, while the 2,2‘ ‘,3‘ ‘-tpa ligand in 3 functions as a terminal ligand, binding to the zinc center through the 3-pyridyl nitrogen atom. All three compounds emit a blue color in solution and in the solid state. The emission maxima for the three compounds in solution are at λ = 422, 426, and 432 nm, respectively. The blue luminescence of the complexes is due to a π* → π transition of the tpa ligand as established by an ab initio calculation on the free ligand 2,2‘,2‘ ‘-tpa and complex 1. Compounds 1 and 2 are fluxional in solution owing to an exchange proce...
