- Tris(trimethylsilyl) titanacyclobutene: A new mild reagent for the conversion of carbonyls to alkenyl silanes
-
Thermolysis of Cp2Ti(CH2SiMe3)2 in the presence of Me3SiC≡CSiMe3 forms tris(trimethylsilyl) titanacyclobutene. Unlike other titanacyclobutenes which undergo insertion with carbonyl compounds, this reagent serves as a precursor to Cp2Ti=CHSiMe3, converting carbonyl compounds to the corresponding alkenyl silanes. This olefination takes place under mild conditions even at room temperature and works with aldehydes, ketones, esters, thioesters and lactones.
- Petasis, Nicos A.,Staszewski, James P.,Fu, Dian-Kui
-
-
Read Online
- Design, Synthesis, and Implementation of Sodium Silylsilanolates as Silyl Transfer Reagents
-
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.
- Yamagishi, Hiroki,Saito, Hayate,Shimokawa, Jun,Yorimitsu, Hideki
-
p. 10095 - 10103
(2021/08/18)
-
- Copper-NHC-Mediated Semihydrogenation and Hydroboration of Alkynes: Enhanced Catalytic Activity Using Ring-Expanded Carbenes
-
A series of two-coordinate copper tert-butoxide complexes bearing five-, six-, and seven-membered ring N-heterocyclic carbenes, prepared by protonolysis of (NHC)CuMes with tBuOH, have been used as catalytic precursors in the semihydrogenation of alkynes with silanes/tBuOH and the hydroboration of alkynes with HBPin. Both processes proceed with high regioselectivity and show enhancements with six- and seven-membered ring carbenes.
- Hall, Jonathan W.,Unson, Darcy M. L.,Brunel, Paul,Collins, Lee R.,Cybulski, Mateusz K.,Mahon, Mary F.,Whittlesey, Michael K.
-
p. 3102 - 3110
(2018/09/12)
-
- METHOD FOR PRODUCING ALKENYLSILANE
-
PROBLEM TO BE SOLVED: To provide a method for producing alkenylsilane that can efficiently produce alkenylsilane. SOLUTION: In the presence of a nickel complex having a phosphine ligand, a Lewis acid, and a base, an alkene having a structure represented by the formula (a) and a chlorosilane having a structure represented by the formula (b) are subjected to a reaction, to efficiently produce alkenylsilane (c). SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
- -
-
Paragraph 0048
(2018/10/31)
-
- Me3Si?SiMe2[oCON(iPr)2?C6H4]: An Unsymmetrical Disilane Reagent for Regio- and Stereoselective Bis-Silylation of Alkynes
-
The air-stable unsymmetrical disilane Me3Si?SiMe2[oCON(iPr)2C6H4] has been developed for bis-silylation of alkynes. This reagent tolerates a range of functional groups, providing Z-vinyl disilanes in
- Xiao, Peihong,Cao, Yanjun,Gui, Yingying,Gao, Lu,Song, Zhenlei
-
supporting information
p. 4769 - 4773
(2018/03/21)
-
- Phenylethenyl-substituted silicones via Heck coupling reaction
-
Systematic studies of several palladium complexes (Pd(OAc)2, [PdCl2(cod)], [Pd2(dba)3], [Pd(PPh3)4], [PdCl(SnCl3)(P{p-Tol}3)2], [Pd2Cl2(SnCl3)su
- Czech, Anna,Ganicz, Tomasz,Noskowska, Ma?gorzata,Stańczyk, W?odzimierz A.,Szelag, Anna
-
experimental part
p. 3386 - 3389
(2010/01/11)
-
- Rhodium-catalysed anomalous dimerization of styrenes involving the cleavage of the ortho C-H bond
-
The dimerization of styrene derivatives in the presence of a rhodium catalyst proceeds to give stilbene derivatives, in which the ortho C-H bond of styrenes is cleaved and functionalized. The Royal Society of Chemistry.
- Tobisu, Mamoru,Hyodo, Isao,Onoe, Masahiro,Chatani, Naoto
-
scheme or table
p. 6013 - 6015
(2009/05/06)
-
- Rapid and efficient entry to vinyl silanes from aldehydes employing a novel metalation-Peterson sequence
-
Bis(trimethylsilyl)chloromethane undergoes a rapid and selective metalation with s-BuLi, yielding the nucleophilic bis(trimethylsilyl)methyl anion and providing a straightforward general entry to vinyl silanes from aromatic, aliphatic and vinyl aldehydes. The Royal Society of Chemistry.
- McNulty, James,Das, Priyabrata
-
p. 1244 - 1245
(2008/12/21)
-
- Selective liquid-phase semihydrogenation of functionalized acetylenes and propargylic alcohols with silica-supported bimetallic palladium-copper catalysts
-
Silica-supported, bimetallic palladium-copper catalysts were prepared in solution under mild conditions by reacting lithium di(4-tolyl)cuprate with palladium acetate in the presence of silica particles. Small bimetallic palladium-copper particles were deposited on the silica surface as confirmed with TEM-EDAX and EXAFS. The new material has been applied as catalyst in the liquid-phase semihydrogenation of mono- and disubstituted alkynes and showed high selectivity toward the cis-alkenes. The influence of addition of quinoline or potassium hydroxide to the semihydrogenation reaction mixture and the effects of exposure of the catalyst to air before use have been investigated. Silica-supported, bimetallic palladium-copper catalysts were prepared in solution under mild conditions by reacting lithium di(4-tolyl)cuprate with palladium acetate in the presence of silica particles. Small bimetallic palladium-copper particles were deposited on the silica surface as confirmed with TEM-EDAX and EXAFS. The new material has been applied as catalyst in the liquid-phase semihydrogenation of mono- and disubstituted alkynes and showed high selectivity toward the cis-alkenes. The influence of addition of quinoline or potassium hydroxide to the semihydrogenation reaction mixture and the effects of exposure of the catalyst to air before use have been investigated.
- Spee,Boersma,Meijer,Slagt,Van Koten,Geus
-
p. 1647 - 1656
(2007/10/03)
-
- TRIMETHYLSILYLDIAZOMETHANE: A CONVENIENT REAGENT FOR THE PREPARATION OF (E)-1-TRIMETHYLSILYL-1-ALKENES
-
The cuprous chloride-catalyzed decomposition of α-trimethylsilyldiazoalkanes gives (E)-1-trimethylsilyl-1-alkenes in high yields.
- Aoyama, Toyohiko,Shioiri, Takayuki
-
p. 6295 - 6296
(2007/10/02)
-
- Synthesis of Trimethylsilyloxy and Hydroxy Compounds from Carbanions and Bis(trimethylsilyl)peroxide.
-
The reactions of bis(trimethylsilyl)peroxide with alkyl, vinyl, alkynyl, aromatic and heteroaromatic anions are described.Depending on the reaction conditions, the trimethylsilyloxy derivatives can be obtained alone or together with the corresponding trimethylsilyl derivatives, which is sometimes the major product.Enolates, generated using magnesium diisopropylamide give the corresponding hydroxycarbonyl compounds in good yields.An attempt to rationalise the above results is given, emphasising the wide use of bis(trimethylsilyl)peroxide in organic synthesis as an electrophilic hydroxylation reagent.
- Camici, Lucia,Dembech, Pasquale,Ricci, Alfredo,Seconi, Giancarlo,Taddei, Maurizio
-
p. 4197 - 4206
(2007/10/02)
-
- Electrochemical Synthesis of Organosilicon Compounds
-
Electrochemical reduction of allyl, aryl, and vinyl halides in the presence of a silylating agent (Me3SiCl, HMe2SiCl, and PhMe2SiCl) in a solution of tetraethylammonium tosylate in dimethylformamide (DMF) gave the corresponding organosilicon compounds.The regioselectivity of the reaction of allylic halides depends on the nature of the silylating agent.Trimethylsilyl and dimethylphenylsilyl groups were introduced to the less substituted end of the allyl group, whereas the dimethylsilyl group was introduced to both ends of the allyl group.High chemoselectivity of the present approach was demonstrated by selectivity monosilylations of p-bromoiodobenzene and p-bromocinnamyl chloride to obtain (p-bromophenyl)trimethylsilane and (p-bromocinnamyl)trimethylsilane, respectively.A mechanism involving a carbanion intermediate is suggested.
- Yoshida, Jun-ichi,Muraki, Katsuhiko,Funahashi, Hirokatsu,Kawabata, Nariyoshi
-
p. 3996 - 4000
(2007/10/02)
-
- NEW METHODS AND REAGENTS IN ORGANIC SYNTHESIS. 37. TRIMETHYLSILYLDIAZOMETHANE. A CONVENIENT REAGENT FOR THE PREPARATION OF VINYLSILANES FROM ALKANESULFONYL CHLORIDES
-
Trimethylsilyldiazomethane reacts smoothly with alkanesulfonyl chlorides in the presence of triethylamine to give vinylsilanes.KEYWORDS - trimethylsilyldiazomethane; vinylsilane; alkanesulfonyl chloride; thermal isomerization; sulfene; episulfone
- Aoyama, Toyohiko,Toyama, Sachio,Tamaki, Naoko,Shioiri, Takayuki
-
p. 2957 - 2959
(2007/10/02)
-