2797-28-6Relevant articles and documents
N-Heterocyclic Iod(az)olium Salts – Potent Halogen-Bond Donors in Organocatalysis
Boelke, Andreas,Kuczmera, Thomas J.,Lork, Enno,Nachtsheim, Boris J.
supporting information, p. 13128 - 13134 (2021/08/09)
This article describes the application of N-heterocyclic iod(az)olium salts (NHISs) as highly reactive organocatalysts. A variety of mono- and dicationic NHISs are described and utilized as potent XB-donors in halogen-bond catalysis. They were benchmarked in seven diverse test reactions in which the activation of carbon- and metal-chloride bonds as well as carbonyl and nitro groups was achieved. N-methylated dicationic NHISs rendered the highest reactivity in all investigated catalytic applications with reactivities even higher than all previously described monodentate XB-donors based on iodine(I) and (III) and the strong Lewis acid BF3.
Lewis Superacidic Catecholato Phosphonium Ions: Phosphorus-Ligand Cooperative C-H Bond Activation
Greb, Lutz,Roth, Daniel,Stephan, Douglas W.,Stirn, Judith
supporting information, p. 15845 - 15851 (2021/10/02)
A series of catecholato phosphonium ions, including the first stable bis(catecholato)-substituted derivatives, are isolated and fully characterized. The cations rank among the most potent literature-known Lewis acids on the Gutmann-Beckett and ion affinit
Alkane-soluble tetra(pentafluorophenyl)borate as well as preparation method and application thereof
-
Paragraph 0131-0134, (2021/10/27)
The invention discloses alkane-soluble tetra(pentafluorophenyl)borate, the structural formula of which is as shown in formula I; in the formula I, R represents 1-hexyl (C6H13), 1-octyl (C8H17), 1-decyl (C10H21) or dodecyl (C12H25), and the substitution position on a benzene ring is ortho-position, meta-position or para-position. The invention also provides a preparation method of the alkane-soluble tetra(pentafluorophenyl)borate and application of the alkane-soluble tetra(pentafluorophenyl)borate in olefin polymerization reaction. The alkane-soluble tetra(pentafluorophenyl)borate provided by the invention not only can be dissolved in a conventional toluene dichloromethane solvent, but also can be dissolved in non-polar straight-chain alkane and cycloalkane solvents. Meanwhile, the compound can serve as a cocatalyst to catalyze olefin polymerization, so that a main catalyst can be efficiently activated to form a high-activity catalyst, ethylene can be catalyzed to polymerize in a non-polar solvent, and a high-performance polyolefin material is prepared.
Diaryl-λ3-chloranes: Versatile Synthesis and Unique Reactivity as Aryl Cation Equivalent
Nakajima, Misuzu,Miyamoto, Kazunori,Hirano, Keiichi,Uchiyama, Masanobu
supporting information, p. 6499 - 6503 (2019/05/06)
We have developed a versatile, high-yield synthesis of diarylchloroniums/λ3-chloranes through the reaction of various chloroarenes with readily prepared mesityldiazonium tetrakis(pentafluorophenyl)borate under mild conditions. The scope of the reaction is broad, including ArCl, ArBr, and ArI. The diarylchloroniums/λ3-chloranes prepared here show unique reactivity in various respects, enabling intermolecular electrophilic arylation reaction of weak nucleophiles, and chlorane-halogane exchange reaction.
Vinyl Carbocations Generated under Basic Conditions and Their Intramolecular C-H Insertion Reactions
Wigman, Benjamin,Popov, Stasik,Bagdasarian, Alex L.,Shao, Brian,Benton, Tyler R.,Williams, Chloé G.,Fisher, Steven P.,Lavallo, Vincent,Houk,Nelson, Hosea M.
supporting information, p. 9140 - 9144 (2019/06/08)
Here we report the surprising discovery that high-energy vinyl carbocations can be generated under strongly basic conditions, and that they engage in intramolecular sp3 C-H insertion reactions through the catalysis of weakly coordinating anion salts. This approach relies on the unconventional combination of lithium hexamethyldisilazide base and the commercially available catalyst, triphenylmethylium tetrakis(pentafluorophenyl)borate. These reagents form a catalytically active lithium species that enables the application of vinyl cation C-H insertion reactions to heteroatom-containing substrates.
Catalytic Access to Indole-Fused Benzosiloles by 2-Fold Electrophilic C-H Silylation with Dihydrosilanes
Omann, Lukas,Oestreich, Martin
supporting information, p. 767 - 776 (2017/04/21)
A protocol for the catalytic synthesis of indole-fused benzosiloles starting from 2-aryl-substituted indoles and dihydrosilanes is reported. Compared to known procedures, this method does not require prefunctionalized starting materials and, hence, allows for a rapid access to those siloles. The net reaction is a 2-fold electrophilic C-H silylation catalyzed by cationic Ru-S complexes. Both reaction steps were separately investigated, and these results eventually led to the development of a two-step procedure. By preparing new Ru-S complexes with different weakly coordinating anions (WCAs), it is also shown that the latter can have a dramatic influence on the outcome of these reactions. Furthermore, the substrate scope of the new method is discussed.
Cooperative Al-H Bond Activation in DIBAL-H: Catalytic Generation of an Alumenium-Ion-Like Lewis Acid for Hydrodefluorinative Friedel-Crafts Alkylation
Forster, Francis,Mets?nen, Toni T.,Irran, Elisabeth,Hrobárik, Peter,Oestreich, Martin
supporting information, p. 16334 - 16342 (2017/11/22)
The Ru-S bond in Ohki-Tatsumi complexes breaks oligomeric DIBAL-H structures into their more reactive monomer. That deaggregation is coupled to heterolytic Al-H bond activation at the Ru-S bond, formally splitting the Al-H linkage into hydride and an alumenium ion. The molecular structure of these Lewis pairs was established crystallographically, revealing an additional Ru-Al interaction next to the Ru-H and Al-S bonds. That bonding situation was further analyzed by quantum-chemical calculations and is best described as a three-center-two-electron (3c2e) donor-acceptor σ(Ru-H) → Al interaction. Despite the extra stabilization of the aluminum center by the interaction with both the sulfur atom and the Ru-H bond, the hydroalane adducts are found to be stronger Lewis acids and electrophiles than the free ruthenium catalyst and DIBAL-H in its different aggregation states. Hence, the DIBAL-H molecule and its Al-H bond are activated by the Ru-S bond, but these hydroalane adducts are not to be mistaken as sulfur-stabilized alumenium ions in a strict sense. The Ohki-Tatsumi complexes catalyze C(sp3)-F bond cleavage with DIBAL-H, and the catalytic setup is applied to hydrodefluorinative Friedel-Crafts alkylations. A broad range of CF3-substituted arenes is efficiently converted into unsymmetrical diarylmethanes with various arenes as nucleophiles. Computed fluoride-ion affinities (FIAs) of the hydroalane adducts as well as DIBAL-H in its aggregation states support this experimental finding.
Addition of Small Electrophiles to N-Heterocyclic-Carbene-Stabilized Disilicon(0): A Revisit of the Isolobal Concept in Low-Valent Silicon Chemistry
Arz, Marius I.,Stra?mann, Martin,Gei?, Daniel,Schnakenburg, Gregor,Filippou, Alexander C.
, p. 4589 - 4600 (2016/05/09)
Protonation and alkylation of (Idipp)S=Si(Idipp) (1) afforded the mixed-valent disilicon(I)-borates [(Idipp)(R)SiII=Si0(Idipp)][B(ArF)4] (1R[B(ArF)4]; R = H, Me, Et; ArF = C6H3-3,5-(CF3)2; Idipp = C[N(C6H3-2,6-iPr2)CH]2) as red to orange colored, highly air-sensitive solids, which were characterized by single-crystal X-ray diffraction, IR spectroscopy and multinuclear NMR spectroscopy. Dynamic NMR studies in solution revealed a degenerate isomerization (topomerization) of the "σ-bonded" tautomers of 1H[B(ArF)4], which proceeds according to quantum chemical calculations via a NHC-stabilized (NHC = N-heterocyclic carbene) disilahydronium ion ("π-bonded" isomer) and is reminiscent of the degenerate rearrangement of carbenium ions formed upon protonation of olefins. The topomerization of 1H[B(ArF)4] provides the first example of a reversible 1,2-H migration along a Si=Si bond observed in a molecular system. In contrast, 1Me[B(ArF)4] adopts a "rigid" structure in solution due to the higher energy required for the interconversion of the "σ-bonded" isomer into a putative NHC-stabilized disilamethonium ion. Addition of alkali metal borates to 1 afforded the alkali metal disilicon(0) borates 1M[BAr4] (M = Li, Ar = C6F5; M = Na, Ar = ArF) as brown, air-sensitive solids. Single-crystal X-ray diffraction analyses and NMR spectroscopic studies of 1M[BAr4] suggest in concert with quantum chemical calculations that encapsulation of the alkali metal cations in the cavity of 1 predominantly occurs via electrostatic cation-π interactions with the Si=Si π-bond and the peripheral NHC aryl rings. Displacement of the [Si(NHC)] fragments by the isolobal fragments [PR] and [SiR]- interrelates the cations [(NHC)(R)Si=Si(NHC)]+ to a series of familiar, multiply bonded Si and P compounds as verified by analyses of their electronic structures.
COLORED COMPOSITION
-
, (2016/01/11)
The present invention is to provide a colored composition having higher heat resistance compared with conventional colored compositions. The present invention further relates to: "a polymer having a monomer unit derived from a monomer which has (i) a cationic rhodamine derivative having, as an counter anion, an anion including an aryl group having an electron-withdrawing substituent and an anion group and (ii) an ethylenically unsaturated bond", "a monomer which has (i) a cationic rhodamine derivative having, as an counter anion, an anion including an aryl group having an electron-withdrawing substituent and an anion group and (ii) an ethylenically unsaturated bond", "a colored composition comprising the above-described polymer or the monomer", and "a colored composition for a color filter comprising the above-described polymer or the monomer".
Determination of hydrophobicity scale of tetraphenylborate and its derivatives by ferrocene based three-phase electrodes
Hu, Keke,Xu, Bing,Shao, Huibo
, p. 36 - 38 (2015/01/16)
In three-phase electrodes (TPE), ferrocene (Fc) was often thought to be useless for ion transfer injection because its oxidized form has very low affinity for organic phase. Instead, lipophilic decamethylferrocene (DMFc) was employed as a better probe for the ion transfer study. However, our present results indicate that the commonly-used DMFc based TPE was not applicable for the transfer of strong hydrophobic tetraphenylborate and its derivatives (TPBs); whereas the developed Fc based TPE can meet this special requirement. Taking this advantage, we firstly evaluate the standard ion transfer energies of these TPBs and get a full knowledge of their hydrophobicity scale, which will benefit the related areas such as hydrophobic ionic liquids and lipophilic anion exchangers.
