116174-30-2Relevant academic research and scientific papers
Probing Intramolecular Electron Transfer in Redox Tag Processes
Maeta, Naoya,Kamiya, Hidehiro,Okada, Yohei
, p. 8519 - 8522 (2019)
Herein, we show that redox tag-guided intermolecular formal [2 + 2] cycloaddition can be used as a probe to investigate intramolecular single-electron transfer (SET) mechanisms. The efficacy of intramolecular SET can be evaluated in association with concomitant carbon-carbon bond formation and/or cleavage, leading to cycloaddition or cross-metathesis. Experimental and theoretical results suggest that the intramolecular SET is under both thermodynamic and kinetic control and can also occur through bonds, not only through space.
Nickel-Catalyzed Negishi-Type Arylation of Trialkylsulfonium Salts
Minami, Hiroko,Nogi, Keisuke,Yorimitsu, Hideki
, p. 1542 - 1546 (2021/09/06)
Negishi-type arylation of trialkylsulfonium salts with arylzinc reagents has been accomplished under nickel catalysis. The use of cyclohexanethiol as an additional ligand was found to be particularly important to promote C-S cleavage. The present reaction accommodates one-pot arylation of dialkyl sulfides by combining with S -methylation with MeOTf. Mechanistic experiments suggest that C-S cleavage would proceed via single-electron transfer (SET) to generate the most stable carbon-centered radical and that the thiolate ligand would promote the C-S cleavage and radical recombination step.
Chromium(II)-Catalyzed Diastereoselective and Chemoselective Csp2-Csp3 Cross-Couplings Using Organomagnesium Reagents
Li, Jie,Ren, Qianyi,Cheng, Xinyi,Karaghiosoff, Konstantin,Knochel, Paul
, p. 18127 - 18135 (2019/11/19)
A simple protocol for performing chromium-catalyzed highly diastereoselective alkylations of arylmagnesium halides with cyclohexyl iodides at ambient temperature has been developed. Furthermore, this ligand-free CrCl2 enables efficient electrophilic alkenylations of primary, secondary, and tetiary alkylmagnesium halides with readily available alkenyl acetates. Moreover, this chemoselective C-C coupling reaction with stereodefined alkenyl acetates proceeds in a stereoretentive fashion. A wide range of functional groups on alkyl iodides and alkenyl acetates are well tolerated, thus furnishing functionalized Csp2-Csp3 coupling products in good yields and high diastereoselectivity. Detailed mechanistic studies suggest that the in situ generated low-valent chromium(I) species might be the active catalyst for these Csp2-Csp3 cross-couplings.
Copper-Catalyzed Boron-Selective C(sp2)-C(sp3) Oxidative Cross-Coupling of Arylboronic Acids and Alkyltrifluoroborates Involving a Single-Electron Transmetalation Process
Ding, Siyi,Xu, Liang,Li, Pengfei
, p. 1329 - 1333 (2016/02/18)
A rapid and highly selective oxidative cross-coupling reaction between readily available and shelf-stable arylboronic acids and primary or secondary potassium alkyltrifluoroborates was devised and developed, which works under mild conditions using copper(II) acetate as the catalyst and silver oxide as the oxidant. Initial experimental results indicate that a single-electron transmetalation process is involved. This approach effectively bypasses the problems associated with the traditional cross-coupling reactions of alkylboronates and thus provides a complementary method in building C(sp2)-C(sp3) bonds.
Copper-Catalyzed Reductive Cross-Coupling of Nonactivated Alkyl Tosylates and Mesylates with Alkyl and Aryl Bromides
Liu, Jing-Hui,Yang, Chu-Ting,Lu, Xiao-Yu,Zhang, Zhen-Qi,Xu, Ling,Cui, Mian,Lu, Xi,Xiao, Bin,Fu, Yao,Liu, Lei
, p. 15334 - 15338 (2016/02/18)
A copper-catalyzed reductive cross-coupling reaction of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides was developed. It provides a practical method for efficient and cost-effective construction of aryl-alkyl and alkyl-alkyl C=C bonds with stereocontrol from readily available substrates. When used in an intramolecular fashion, the reaction enables convenient access to various substituted carbo- or heterocycles, such as 2,3-dihydrobenzofuran and benzochromene derivatives.
One-step cross-coupling reaction of functionalized alkyl iodides with aryl halides by the use of an electrochemical method
Kurono, Nobuhito,Sugita, Kazuya,Takasugi, Shingo,Tokuda, Masao
, p. 6097 - 6108 (2007/10/03)
Organozinc compounds of functionalized alkyl iodide carrying an alkoxycarbonyl, cyano or alkenyl group were prepared in high yields under mild conditions (0°C-r.t., 10min in DMF) by the reaction of iodides with an electrogenerated reactive zinc (EGZn). Cross-coupling of the organozinc compounds with various aryl halides in the presence of 5 mol% Pd(P(o- Tol)3)2Cl2 in THF gave the corresponding cross-coupled products in moderate to high yields. These cross-coupling reactions can be also achieved in one step and in one pot by the use of an electrochemical method utilizing a Pt cathode and Zn anode.
Hole transfer promoted hydrogenation: One-electron oxidation as a strategy for selective reduction of π-bonds
Mirafzal, Gholam A.,Liu, Jianping,Bauld, Nathan L.
, p. 6072 - 6077 (2007/10/02)
One-electron oxidation is developed as a strategy for selective and efficient reduction of relatively ionizable functionalities, including conjugated dienes, styrenes, vinyl sulfides, aromatics, and even strained σ-bonds. Reduction is highly sensitive to substrate ionizability and permits selective reduction of the more ionizable function in a difunctional context. Ionization of the substrates to cation radicals is effected via the mild hole transfer agent tris(4-bromophenyl)aminium hexachloroantimonate, and subsequent reduction of the cation radicals is accomplished by tributyltin hydride. The new reduction conditions provide a novel route for generating free radicals which may prove useful in the field of radical cyclizations. This is especially attractive in the case of phenyl vinyl sulfides since the phenylthio group, which remains intact subsequent to cyclization, provides versatile functionality for further synthetic operations.
