54607-03-3Relevant academic research and scientific papers
Nickel-catalyzed Heck reaction of cycloalkenes using aryl sulfonates and pivalates
Zhou, Jianrong Steve,Huang, Xiaolei,Teng, Shenghan,Chi, Yonggui Robin
supporting information, p. 3933 - 3936 (2021/04/26)
Nickel-catalyzed Heck reaction of cycloalkenes delivers unusual conjugated arylated isomers. Nickel(0) catalysts ligated by chelating dialkylphosphines effectively activate not only aryl triflates as electrophiles, but also less reactive aryl mesylates, t
Ni-Catalyzed Cross-Coupling of Dimethyl Aryl Amines with Arylboronic Esters under Reductive Conditions
Cao, Zhi-Chao,Xie, Si-Jun,Fang, Huayi,Shi, Zhang-Jie
supporting information, p. 13575 - 13579 (2018/10/24)
Herein, we reported a successful Suzuki-Miyaura coupling of dimethyl aryl amines to forge biaryl skeleton via Ni catalysis in the absence of directing groups and preactivation. This transformation proceeded with high efficiency in the presence of magnesium. Preliminary mechanism studies demonstrated dual roles of magnesium: (i) a reductant that reduced Ni(II) species to active Ni(I) catalyst; (ii) a unique promoter that facilitated the Ni(I)/Ni(III) catalytic cycle.
Cross-Coupling of Organolithium with Ethers or Aryl Ammonium Salts by C?O or C?N Bond Cleavage
Yang, Ze-Kun,Wang, Dong-Yu,Minami, Hiroki,Ogawa, Hiroyuki,Ozaki, Takashi,Saito, Tatsuo,Miyamoto, Kazunori,Wang, Chao,Uchiyama, Masanobu
supporting information, p. 15693 - 15699 (2016/10/25)
Various aryl-, alkenyl-, and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C?O bond to afford cross-coupled products, catalyzed by commercially available [Ni(cod)2] (cod=1,5-cyclooctadiene) catalysts with N-heterocyclic carbene (NHC) ligands. Furthermore, the coupling reaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C?N bond cleavage in the presence of a [Pd(PPh3)2Cl2] catalyst. These methods enable selective sequential functionalizations of arenes having both C?N and C?O bonds in one pot.
Nickel-catalyzed reductive cleavage of aryl alkyl ethers to arenes in absence of external reductant
Tobisu, Mamoru,Morioka, Toshifumi,Ohtsuki, Akimichi,Chatani, Naoto
, p. 3410 - 3414 (2015/05/27)
The reductive cleavage of the C-O bonds of aryl ethers has great potential in organic synthesis. Although several catalysts that can promote the reductive cleavage of aryl ethers have been reported, all such systems require the use of an external reductant, e.g., hydrosilane or hydrogen. Here, we report the development of a new nickel-based catalytic system that can cleave the C-O bonds of ethers in the absence of an external reductant. The hydrogen atom required in this new reductive cleavage reaction is provided by the alkoxy group of the substrate, which serves as an internal reductant. The absence of an external reductant enables the unique chemoselectivity, i.e., the selective reduction of an alkoxy group over alkenes and ketones. This journal is
Enantioselective photoredox catalysis enabled by proton-coupled electron transfer: Development of an asymmetric aza-pinacol cyclization
Rono, Lydia J.,Yayla, Hatice G.,Wang, David Y.,Armstrong, Michael F.,Knowles, Robert R.
supporting information, p. 17735 - 17738 (2014/01/06)
The first highly enantioselective catalytic protocol for the reductive coupling of ketones and hydrazones is reported. These reactions proceed through neutral ketyl radical intermediates generated via a concerted proton-coupled electron transfer (PCET) event jointly mediated by a chiral phosphoric acid catalyst and the photoredox catalyst Ir(ppy)2(dtbpy)PF6. Remarkably, these neutral ketyl radicals appear to remain H-bonded to the chiral conjugate base of the Bronsted acid during the course of a subsequent C-C bond-forming step, furnishing syn 1,2-amino alcohol derivatives with excellent levels of diastereo- and enantioselectivity. This work provides the first demonstration of the feasibility and potential benefits of concerted PCET activation in asymmetric catalysis.
Single electron transfer-induced cross-coupling reaction of alkenyl halides with aryl Grignard reagents
Shirakawa, Eiji,Watabe, Ryo,Murakami, Takuya,Hayashi, Tamio
supporting information, p. 5219 - 5221 (2013/06/27)
Alkenyl halides were found to undergo coupling with aryl Grignard reagents to give the corresponding styrene derivatives in a stereo-retained manner. The cross-coupling reaction is considered to proceed through a single electron transfer mechanism.
Achieving vinylic selectivity in Mizoroki-heck reaction of cyclic olefins
Wu, Xiaojin,Lu, Yunpeng,Hirao, Hajime,Zhou, Jianrong
, p. 6014 - 6020 (2013/06/26)
In Heck reactions of cyclic olefins, the products usually have aryl groups that end up at the allylic and/or homoallylic position. We herein report new selectivity that adds aryl groups to the vinylic position. Cyclic olefins of various ring size worked well. The desired isomers were produced by palladium-hydride-catalyzed isomerization of the initial products. Thus, a specific catalyst must be used so that it can perform two jobs under one set of reaction conditions. Copyright
Selective arylation at the vinylic site of cyclic olefins
Wu, Xiaojin,Zhou, Jianrong
supporting information, p. 4794 - 4796 (2013/06/05)
Cyclic olefins usually give Heck products having an aryl ring residing at the allylic or homoallylic position. We describe herein a new method that allows arylation at the vinylic position of various cyclic olefins.
A peptide-embedded trifluoromethyl ketone catalyst for enantioselective epoxidation
Romney, David K.,Miller, Scott J.
supporting information; experimental part, p. 1138 - 1141 (2012/05/04)
The development of peptide-based oxidation catalysts that use a transiently generated dioxirane as the chemically active species is reported. The active catalyst is a chiral trifluoromethyl ketone (Tfk) with a pendant carboxylic acid that can be readily incorporated into a peptide. These peptides were capable of epoxidizing alkenes in high yield (up to 89%) and enantiomeric ratios (er) ranging from 69.0:31.0 to 91.0:9.0, depending on the alkene substitution pattern.
Cross-coupling of aryl/alkenyl silyl ethers with grignard reagents through nickel-catalyzed CO bond activation
Zhao, Fei,Yu, Da-Gang,Zhu, Ru-Yi,Xi, Zhenfeng,Shi, Zhang-Jie
supporting information; experimental part, p. 1001 - 1003 (2011/12/05)
CO activation and its application have drawn much attention since oxygen-based electrophiles are easily available, less toxic, and more environmentally benign. This letter presents systematically results on the Ni-catalyzed KumadaTamaoCorriu coupling based on siloxy arenes/alkenes, which provides a new strategy of silyl protection/CC bond formation sequence in organic synthesis.
