40036-62-2Relevant articles and documents
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.
Copper-catalyzed oxidative homo- and cross-coupling of grignard reagents using diaziridinone
Zhu, Yingguang,Xiong, Tao,Han, Wenyong,Shi, Yian
supporting information, p. 6144 - 6147 (2015/01/09)
Transition-metal-catalyzed cross-coupling reactions are among the most powerful synthetic transformations. This paper describes an efficient copper-catalyzed homo- and cross-coupling of Grignard reagents with di-tert-butyldiaziridinone as oxidant under mild conditions, giving the coupling products in good to excellent yields. The reaction process has a broad substrate scope and is also effective for the C(sp)-C(sp3) coupling.
Arylsulfonylacetylenes as alkynylating reagents
Marzo, Leyre,Aleman, Jose,Garcia Ruano, Jose Luis
, p. 403 - 407 (2013/07/26)
The unexpected anti-Michael addition of RLi to β-substituted sulfonylacetylenes, followed by in situ elimination of the ion sulfinate, allows the alkynylation of C(sp2) and C(sp3). Aryl and heteroaryl acetylenes, enynes, and mono and dialkyl alkynes can be obtained in very high yields under very mild conditions, avoiding the use of transition metals as catalysts and, in many cases, haloderivatives as starting materials. Furthermore, the use of lithium 2-p-tolylsulfinyl benzylcarbanions as nucleophiles of these reactions allows their stereocontrolled alkynylation, affording enantiomerically pure alkynes or enantioenriched allenes depending on the protonating agent (NH4Cl or H2O).
Expanding the scope of arylsulfonylacetylenes as alkynylating reagents and mechanistic insights in the formation of Csp2-Csp and Csp 3-Csp bonds from organolithiums
Garcia Ruano, Jose Luis,Aleman, Jose,Marzo, Leyre,Alvarado, Cuauhtemoc,Tortosa, Mariola,Diaz-Tendero, Sergio,Fraile, Alberto
supporting information; experimental part, p. 8414 - 8422 (2012/07/27)
We describe the unexpected behavior of the arylsulfonylacetylenes, which suffer an "anti-Michael" addition of organolithiums producing their alkynylation under very mild conditions. The broad scope, excellent yields, and simplicity of the experimental procedure are the main features of this methodology. A rational explanation of all these results can be achieved by theoretical calculations, which suggest that the association of the organolithiums to the electrophile is a previous step of their intramolecular attack and is responsible for the unexpected "anti-Michael" reactions observed for substituted sulfonylacetylenes. A calculated conclusion: A new transition-metal-free strategy for the synthesis of any kind of alkynyl derivatives in high yields in the reaction of organolithium species with arylsulfonylacetylenes is presented (see scheme). Theoretical calculations provide a rational explanation and suggest that association of the organolithium to the electrophile is a previous step of their intramolecular attack and is responsible for the "anti-Michael" reaction. Copyright
Highly chemoselective calcium-catalyzed propargylic deoxygenation
Meyer, Vera J.,Niggemann, Meike
supporting information; experimental part, p. 4687 - 4691 (2012/05/04)
A calcium-catalyzed direct reduction of propargylic alcohols and ethers has been accomplished by using triethylsilane as a nucleophilic hydride source. At room temperature a variety of secondary propargylic alcohols was deoxygenated to the corresponding h
Vinylic Organoboranes. 1. A Convenient Synthesis of Acetylenes via the Reaction of Lithium (1-Alkynyl)organoborates with Iodine
Suzuki, Akira,Miyaura, Norio,Abiko, Shigeo,Itoh, Mitsuomi,Midland, M., Mark,et al.
, p. 4507 - 4511 (2007/10/02)
Lithium (1-alkynyl)organoborates, readily prepared from organoboranes and lithium acetylides, undergo a facile reaction at low temperature with iodine to for internal acetylenes in high yield.Unlike conventional methods for the preparation of acetylenes via nucleophilic displacement, the reaction is applicable to both primary and secondary as well as aromatic and functionally substituted groups.The use of lithium acetylide-ethylenediamine form the formation of the organoborate extends the reaction to terminal acetylenes.This reaction occurs with complete retention of the configuration about the boron-carbon bond.The procedure, with its exceptionally broad applicability, provides a simple, general route to internal and terminal acetylenes.