35843-79-9Relevant articles and documents
Ru-catalysed C(sp2)-H vinylation/annulation of benzoic acids and alkynes: rapid access to medium-sized lactones
Hu, Xiao-Qiang,Liu, Zi-Kui,Hou, Ye-Xing,Zhang, Guodong,Gao, Yang
supporting information, p. 1113 - 1116 (2021/02/06)
An unprecedented ruthenium catalysed [4+4] annulation of readily available benzoic acids and alkynes is reported for the first time. The carboxylate group acts as both a directing group and an internal nucleophilic reagent to facilitate a C(sp2
Enabling the Use of Alkyl Thianthrenium Salts in Cross-Coupling Reactions by Copper Catalysis
Chen, Cheng,Lu, Hongjian,Shi, Zhuangzhi,Wang, Minyan,Zhao, Binlin
supporting information, p. 21756 - 21760 (2021/08/30)
Alkyl groups are one of the most widely used groups in organic synthesis. Here, a a series of thianthrenium salts have been synthesized that act as reliable alkylation reagents and readily engage in copper-catalyzed Sonogashira reactions to build C(sp3)?C(sp) bonds under mild photochemical conditions. Diverse alkyl thianthrenium salts, including methyl and disubstituted thianthrenium salts, are employed with great functional breadth, since sensitive Cl, Br, and I atoms, which are poorly tolerated in conventional approaches, are compatible. The generality of the developed alkyl reagents has also been demonstrated in copper-catalyzed Kumada reactions.
A Commercially Available and User-Friendly Catalyst for Hydroamination Reactions under Technical Conditions
Zelenay, Benjamin,Munton, Peter,Tian, Xiaojie,Díez-González, Silvia
, p. 4725 - 4730 (2019/08/01)
The activity of a simple, commercially available copper salt, [Cu(NCMe)4](BF4) in intramolecular hydroamination reactions of alkynes and allenes is presented. Reactions were successfully carried out in technical acetonitrile in the presence of air. While attempts of alkene hydroamination failed, this catalyst was also found active in intermolecular aza-Michael reactions.
Alkylation of Terminal Alkynes under Zinc Lewis Acid Catalysis and Its Mechanistic Studies
Osano, Mana,Kida, Takeru,Yonekura, Kyohei,Tsuchimoto, Teruhisa
supporting information, p. 2825 - 2831 (2019/04/13)
With a zinc Lewis acid catalyst and proton sponge in toluene, terminal alkynes were found to undergo the alkylation by alkyl triflates to provide unsymmetrical internal alkynes. This is the first example that a simple alkyl chain other than benzylic and norbornyl units can be introduced onto the alkynyl carbon atom under Lewis acid catalysis. Mechanistic studies revealed that the activation of the alkyne by the zinc Lewis acid and proton sponge is the trigger of the reaction to give a monoalkynylzinc species, which successively reacts with the alkyl triflate to afford the internal alkyne. A radical pathway is unlikely in this system. (Figure presented.).
Titanium-Promoted Cross-Coupling for the Selective Synthesis of Polysubstituted, Conjugated Amides
Chenniappan, Vinoth Kumar,Rahaim, Ronald J.
, p. 5090 - 5093 (2016/10/14)
α,β-Unsaturated amides are important building blocks and are key structural elements in a number of biologically active natural products. Despite their importance and prevalence, few methods exist to prepare conjugated amides directly and modularly. To address this gap, a titanium-promoted coupling of alkynes and isocyanates has been developed. The method is highly stereoselective, producing only the E isomer with good chemoselectivity and regioselectivity (>95/5), for unsymmetrical internal alkynes that contain a steric bias. The reactive titanacyclopentene intermediate formed from the coupling of the alkyne and isocyanate was additionally reacted with various electrophiles to access tetrasubstituted enamides.
Ni-Catalyzed Carboxylation of Unactivated Alkyl Chlorides with CO2
B?rjesson, Marino,Moragas, Toni,Martin, Ruben
supporting information, p. 7504 - 7507 (2016/07/06)
A catalytic carboxylation of unactivated primary, secondary, and tertiary alkyl chlorides with CO2 at atmospheric pressure is described. This protocol represents the first intermolecular cross-electrophile coupling of unactivated alkyl chlorides, thus leading to new knowledge in the cross-coupling arena.
Copper-catalyzed highly selective semihydrogenation of non-polar carbon-carbon multiple bonds using a silane and an alcohol
Semba, Kazuhiko,Fujihara, Tetsuaki,Xu, Tinghua,Terao, Jun,Tsuji, Yasushi
supporting information; experimental part, p. 1542 - 1550 (2012/08/08)
A copper catalyst bearing a suitable Xantphos derivative or NHC ligand was found to be highly efficient for the selective semihydrogenation of non-polar unsaturated compounds using a mixture of a silane and an alcohol as reducing agent. The catalytic system was useful for the selective semihydrogenation of internal alkynes to (Z)-alkenes with suppression of overreduction to the corresponding alkanes. Furthermore, semihydrogenations of terminal alkyne, 1,2-diene, 1,3-diene, 1,3-enyne and 1,3-diyne systems were also achieved selectively. Copyright
Sonogashira couplings of aryl bromides: Room temperature, water only, no copper
Lipshutz, Bruce H.,Chung, David W.,Rich, Brian
supporting information; experimental part, p. 3793 - 3796 (2009/07/01)
(Chemical Equation Presented) Cross-coupling reactions between lipophilic terminal alkynes and aryl bromides can be catalyzed by ligated Pd, in the absence of copper, In pure water at ambient temperatures. Small amounts of the nonionic amphiphile PTS assi
Intramolecular carbolithiation promoted by a DTBB-catalysed chlorine-lithium exchange
Yus, Miguel,Ortiz, Rosa,Huerta, Fernando F.
, p. 8525 - 8542 (2007/10/03)
The reaction of 6-chlorohex-1-ene 1 with lithium powder and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB, 5% molar) in THF at -78°C gives the corresponding organolithium intermediate 2, which by reaction with different electrophiles affords, aft
Formation and behavior of intramolecular N-(styrylalkyl)aniline exciplexes
Lewis, Frederick D.,Wagner-Brennan, Jill M.,Miller, Alan M.
, p. 595 - 604 (2007/10/03)
The photophysical and photochemical behavior of several aniline spacer - styrene molecules in which the spacer is a short polymethylene chain has been investigated. Long wavelength excitation selectively excites the aniline chromophore which undergoes intramolecular quenching by the styrene to yield an intramolecular exciplex. Exciplex fluorescence is observed for both of the tertiary anilines investigated and for one of the three secondary anilines. More rapid exciplex formation in nonpolar vs. polar solvents is attributed to the necessity of desolvating the polar aniline singlet in polar solvents. Intramolecular adduct formation is the major photochemical process for the secondary anilines, but is highly inefficient for the tertiary anilines. The behavior of the intramolecular aniline-styrene exciplexes is compared to that of the styrene-amine exciplexes previously investigated in this laboratory.
