17876-90-3Relevant articles and documents
Preparation method of aromatic silicon organic compound
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Paragraph 0076-0079, (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.
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.
Sodium silylsilanolate enables nickel-catalysed silylation of aryl chlorides
Hitoshio, Kenshiro,Yamagishi, Hiroki,Shimokawa, Jun,Yorimitsu, Hideki
supporting information, p. 6867 - 6870 (2021/07/19)
Structurally diverse aryl chlorides were silylated with sodium silylsilanolate reagents in the presence of a Ni(cod)2catalyst complexed with a phosphine ligand; PMe2Ph for electron-rich substrates, and PCy2Ph for electron-deficient ones. The mild reaction conditions allowed the silylation of various aryl chlorides including functionalised drug molecules.
Meta C-H Arylation of Electron-Rich Arenes: Reversing the Conventional Site Selectivity
Liu, Luo-Yan,Qiao, Jennifer X.,Yeung, Kap-Sun,Ewing, William R.,Yu, Jin-Quan
supporting information, p. 14870 - 14877 (2019/10/02)
Controlling site selectivity of C-H activation without using a directing group remains a significant challenge. While Pd(II) catalysts modulated by a mutually repulsive pyridine-type ligand have been shown to favor the relatively electron-rich carbon centers of arenes, reversing the selectivity to favor palladation at the relatively electron-deficient positions has not been possible. Herein we report the first catalytic system that effectively performs meta C-H arylation of a variety of alkoxy aromatics including 2,3-dihydrobenzofuran and chromane with exclusive meta site selectivity, thus reversing the conventional site selectivity governed by native electronic effects. The identification of an effective ligand and modified norbornene (NBE-CO2Me), as well as taking advantage of the statistics, are essential for achieving the exclusive meta selectivity.
Probing for a leaving group effect on the generation and reactivity of phenyl cations
Abitelli, Erika,Protti, Stefano,Fagnoni, Maurizio,Albini, Angelo
, p. 3501 - 3507 (2012/06/15)
Phenyl cations are smoothly generated by the photoheterolytic cleavage of an Ar-LG bond (LG = leaving group). With the aim of evaluating the scope of the method, a series of 4-methoxy-2-(trimethylsilyl)phenyl derivatives (sulfonic, LG = MeSO3 and CF3SO3, phosphate, LG = (EtO) 2(O)PO esters and the corresponding chloride) have been compared as probes for evaluating the leaving group ability. The photocleavage was a general reaction, with the somewhat surprising order (EtO)2(O)PO ～ Cl > CF3SO3 > MeSO3 (φ = 0.50 to 0.16 in CF3CH2OH and lower values in MeCN-H2O). The ensuing reactions did not depend on the LGs but only on the structure of the phenyl cation (the silyl group tuned the triplet to singlet intersystem crossing and the electrophilicity) and on the medium (formation of a complex with water slowed the electrophilic reactions).
Palladium-catalyzed intermolecular coupling of 2-silylaryl bromides with alkynes: Synthesis of benzosiloles and heteroarene-fused siloles by catalytic cleavage of the C(sp3)-Si bond
Liang, Yun,Geng, Weizhi,Wei, Junnian,Xi, Zhenfeng
supporting information; experimental part, p. 1934 - 1937 (2012/03/26)
Unusual split: A wide variety of benzosiloles and derivatives are obtained by the Pd-catalyzed intermolecular coupling of 2-silylaryl bromides and alkynes and the accompanying selective cleavage of the C(sp3)-Si bonds as a key step (see scheme). The product spectrum includes benzosiloles, benzothiophene-fused siloles, ladder-type π-conjugated benzosiloles, and thiophene-bridged 2,5-bisbenzosiloles.
Rhodium-catalyzed alkenylation of nitriles via silicon-assisted C-CN bond cleavage
Kita, Yusuke,Tobisu, Mamoru,Chatani, Naoto
supporting information; experimental part, p. 1864 - 1867 (2010/10/02)
Rhodium-catalyzed Mizoroki-Heck type reaction of nitriles via the cleavage of C-C bonds is described. Orthogonal and iterative functionalizations of arenes were also demonstrated by combining the present and conventional halide-based cross-coupling reacti
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.
The β effect of silicon in phenyl cations
Dichiarante, Valentina,Salvaneschi, Andrea,Protti, Stefano,Dondi, Daniele,Fagnoni, Maurizio,Albini, Angelo
, p. 15919 - 15926 (2008/09/20)
Irradiation of chloroanisoles, phenols, and N,N-dimethylanilines bearing a trimethylsilyl (TMS) group in the ortho position with respect to the chlorine atom caused photoheterolysis of the Ar-Cl bond and formation of the corresponding ortho-trimethylsilylphenyl cations in the triplet state. The β effect of silicon on these intermediates has been studied by comparing the resulting chemistry in alcoholic solvents with that of the silicon-free analogues and by computational analysis (at the UB3LYP/6-311+G(2d,p) level in MeOH). TMS groups little affect the photophysics and the photocleavage of the starting phenyl chlorides, while stabilizing the phenyl cations, both in the triplet (ca. 4 kcal/mol per group) and, dramatically, in the singlet state (9 kcal/mol). As a result, although triplet phenyl cations are the first formed species, intersystem crossing to the more stable singlets is favored with chloroanisoles and phenols. Indeed, with these compounds, solvent addition to give aryl ethers (from the singlet) competed efficiently with reduction or arylation (from the triplet). In the case of the silylated 4-chloro-N,N- dimethylaniline, the triplet cation remained in the ground state and trapping by π nucleophiles remained efficient, though slowed by the steric bulk of the TMS group. In alcohols, the silyl group was eliminated via a photoinduced protiodesilylation during the irradiation. Thus, the silyl group could be considered as a directing, photoremovable group that allowed shifting to the singlet phenyl cation chemistry and was smoothly eliminated in the same one-pot procedure.
The tertiary sulfonamide as a latent directed-metalation group: Ni 0-catalyzed reductive cleavage and cross-coupling reactions of aryl sulfonamides with Grignard reagents
Milburn, Robert R.,Snieckus, Victor
, p. 888 - 891 (2007/10/03)
A mild method for the Ni0-catalyzed hydrodesulfamoylation (see scheme, B) of aryl sulfonamides (1→2) with iPr2Mg or iPrMgCl as β-hydride transfer sources can be linked with directed ortho metalation (A and C) to give meta-substituted aromatics 2. Cross-coupling process with alkyl and aryl Grignard reagents furnish disubstituted benzenes and bi- and teraryl compounds.
