455-17-4Relevant articles and documents
Design, Synthesis, and Implementation of Sodium Silylsilanolates as Silyl Transfer Reagents
Yamagishi, Hiroki,Saito, Hayate,Shimokawa, Jun,Yorimitsu, Hideki
, p. 10095 - 10103 (2021/08/18)
There is an increasing demand for facile delivery of silyl groups onto organic bioactive molecules. One of the common methods of silylation via a transition-metal-catalyzed coupling reaction employs hydrosilane, disilane, and silylborane as major silicon sources. However, the labile nature of the reagents or harsh reaction conditions sometimes render them inadequate for the purpose. Thus, a more versatile alternative source of silyl groups has been desired. We hereby report a design, synthesis, and implementation of storable sodium silylsilanolates that can be used for the silylation of aryl halides and pseudohalides in the presence of a palladium catalyst. The developed method allows a late-stage functionalization of polyfunctionalized compounds with a variety of silyl groups. Mechanistic studies indicate that (1) a nucleophilic silanolate attacks a palladium center to afford a silylsilanolate-coordinated arylpalladium intermediate and (2) a polymeric cluster of silanolate species assists in the intramolecular migration of silyl groups, which would promote an efficient transmetalation.
Preparation method of aromatic silicon organic compound
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Paragraph 0056-0059, (2021/07/08)
The invention provides a preparation method of an aromatic silicon organic compound. The aromatic silicon organic compound is a compound as shown in a formula 3 shown in the specification, the aromatic silicon organic compound is prepared by reacting a compound as shown in a formula 1 with a compound as shown in a formula 2, and the reaction formula is as shown in the specification. In the formulas, a is selected from any integer of 0-5, n is selected from any integer of 1-6, R is selected from one of alkyl, alkoxy, fluorine, trifluoromethyl and trifluoromethoxy; m is any integer selected from 1-3, and R2 is selected from C1-C6 alkyl; a catalyst used in the reaction is MIc, MIc is iodized salt, M is metal ion, and c is selected from 1 or 2 according to the valence state of M; and magnesium is added in the reaction process. The method has the advantages of low cost, effective avoidance of heavy metal residues, simplicity and convenience in operation, high yield, mild reaction conditions and easiness in industrialization.
Oxidative Addition of Alkenyl and Alkynyl Iodides to a AuI Complex
Bower, John F.,Cadge, Jamie A.,Russell, Christopher A.,Sparkes, Hazel A.
supporting information, p. 6617 - 6621 (2020/03/13)
The first isolated examples of intermolecular oxidative addition of alkenyl and alkynyl iodides to AuI are reported. Using a 5,5′-difluoro-2,2′-bipyridyl ligated complex, oxidative addition of geometrically defined alkenyl iodides occurs readily, reversibly and stereospecifically to give alkenyl-AuIII complexes. Conversely, reversible alkynyl iodide oxidative addition generates bimetallic complexes containing both AuIII and AuI centers. Stoichiometric studies show that both new initiation modes can form the basis for the development of C?C bond forming cross-couplings.
Modular and Selective Arylation of Aryl Germanes (C?GeEt3) over C?Bpin, C?SiR3 and Halogens Enabled by Light-Activated Gold Catalysis
Dahiya, Amit,Fricke, Christoph,Funes-Ardoiz, Ignacio,Gevondian, Avetik G.,Schoenebeck, Franziska,Sherborne, Grant J.
supporting information, p. 15543 - 15548 (2020/06/22)
Selective C (Formula presented.) –C (Formula presented.) couplings are powerful strategies for the rapid and programmable construction of bi- or multiaryls. To this end, the next frontier of synthetic modularity will likely arise from harnessing the coupling space that is orthogonal to the powerful Pd-catalyzed coupling regime. This report details the realization of this concept and presents the fully selective arylation of aryl germanes (which are inert under Pd0/PdII catalysis) in the presence of the valuable functionalities C?BPin, C?SiMe3, C?I, C?Br, C?Cl, which in turn offer versatile opportunities for diversification. The protocol makes use of visible light activation combined with gold catalysis, which facilitates the selective coupling of C?Ge with aryl diazonium salts. Contrary to previous light-/gold-catalyzed couplings of Ar–N2+, which were specialized in Ar–N2+ scope, we present conditions to efficiently couple electron-rich, electron-poor, heterocyclic and sterically hindered aryl diazonium salts. Our computational data suggest that while electron-poor Ar–N2+ salts are readily activated by gold under blue-light irradiation, there is a competing dissociative deactivation pathway for excited electron-rich Ar–N2+, which requires an alternative photo-redox approach to enable productive couplings.
Fluorination of arylboronic esters enabled by bismuth redox catalysis
Planas, Oriol,Wang, Feng,Leutzsch, Markus,Cornella, Josep
, p. 313 - 317 (2020/01/28)
Bismuth catalysis has traditionally relied on the Lewis acidic properties of the element in a fixed oxidation state. In this paper, we report a series of bismuth complexes that can undergo oxidative addition, reductive elimination, and transmetallation in a manner akin to transition metals. Rational ligand optimization featuring a sulfoximine moiety produced an active catalyst for the fluorination of aryl boronic esters through a bismuth (III)/bismuth (V) redox cycle. Crystallographic characterization of the different bismuth species involved, together with a mechanistic investigation of the carbonfluorine bond-forming event, identified the crucial features that were combined to implement the full catalytic cycle.
New transmetalation reagents for the gold-catalyzed visible light-enabled C(sp or sp2)-C(sp2) cross-coupling with aryldiazonium salts in the absence of a photosensitizer
Witzel, Sina,Sekine, Kohei,Rudolph, Matthias,Hashmi, A. Stephen K.
supporting information, p. 13802 - 13804 (2018/12/14)
The scope of photosensitizer-free visible light-driven gold-catalyzed cross-coupling was evaluated by a wide variety of organoboron and organosilicon species using four equivalents of aryldiazonium salts and (4-CF3-C6H4)3PAuCl in MeOH. In addition, a C(sp or sp2)-C(sp2) cross-coupling of organotrimethylsilanes and aryldiazonium salts was investigated. The reactions can be conducted under very mild reaction conditions, with a reduced amount of aryldiazonium salt (1.2 equiv.) by using a catalytic amount of Ph3PAuNTf2 in MeCN under irradiation with blue LEDs at room temperature.
Oxidative 1,2-Difunctionalization of Ethylene via Gold-Catalyzed Oxyarylation
Harper, Matthew J.,Emmett, Edward J.,Bower, John F.,Russell, Christopher A.
supporting information, p. 12386 - 12389 (2017/09/22)
Under the conditions of oxidative gold catalysis, exposure of ethylene to aryl silanes and alcohols generates products of 1,2-oxyarylation. This provides a rare example of a process that allows catalytic differential 1,2-difunctionalization of this feedstock chemical.
Palladium-catalyzed direct CH bond arylation of simple arenes with aryltrimethylsilanes
Funaki, Kenji,Kawai, Hiroshi,Sato, Tetsuo,Oi, Shuichi
supporting information; experimental part, p. 1050 - 1052 (2011/12/05)
Direct CH bond arylation of arenes with aryltrimethylsilanes catalyzed by PdCl2 in the presence of CuCl2 as an oxidant has been developed. In addition to the role as the oxidant, CuCl2 is found to be necessary for the selective crosscoupling reaction.
Formation of silicon-carbon bonds by photochemical irradiation of (η5-C5H5)Fe(CO)2SiR3 and (η5-C5H5)Fe(CO)2Me to Obtain R3SiMe
Fortier, Skye,Zhang, Yongqiang,Sharma, Hemant K.,Pannell, Keith H.
experimental part, p. 1041 - 1044 (2010/04/25)
Photochemical irradiation of an equimolar mixture of (η5 -C5H5)Fe(CO)2SiR3, FpSiR 3, and FpMe leads to the efficient formation of the silicon-carbon-coupled product R3SiMe, R3 = Me 3, Me2Ph, MePh2, Ph3, ClMe 2, Cl2Me, Cl3, Me2Ar (Ar = C 6H4-p-X, X = F, OMe, CF3, NMe2). Similar chemistry occurs with related germyl and stannyl complexes at slower rates, Si > Ge Sn. Substitution of an aryl hydrogen to form FpSiMe2C6H4-p-X has little effect on the rate of the reaction, whereas progressive substitution of methyl groups on silicon by Cl slows the process. Also, changing FpMe to FpCH2SiMe3 dramatically slows the reaction as does the use of (η5-C 5Me5)Fe(CO)2 derivatives. A mechanism involving the initial formation of the 16e intermediate (η5-C 5H5)Fe(CO)Me followed by oxidative addition of the Fe-Si bond accounts for the experimental results obtained.
Rhodium-catalyzed silylation and intramolecular arylation of nitriles via the silicon-assisted cleavage of carbon-cyano bonds
Tobisu, Mamoru,Kita, Yusuke,Ano, Yusuke,Chatani, Naoto
supporting information; experimental part, p. 15982 - 15989 (2009/05/16)
A rhodium-catalyzed silylation reaction of carbon - cyano bonds using disilane has been developed. Under these catalytic conditions, carbon-cyano bonds in aryl, alkenyl, allyl, and benzyl cyanides bearing a variety of functional groups can be silylated. The observation of an enamine side product in the silylation of benzyl cyanides and related stoichiometric studies indicate that the carbon-cyano bond cleavage proceeds through the deinsertion of silyl isocyanide from η2-iminoacyl complex B. Knowledge gained from these studies has led to the development of a new intramolecular biaryl coupling reaction in which aryl cyanides and aryl chlorides are cross-coupled.
