53806-72-7Relevant academic research and scientific papers
Direct functionalization of tetrahydrofuran and 1,4-dioxane: Nickel-catalyzed oxidative C(sp3)-H arylation
Liu, Dong,Liu, Chao,Li, Heng,Lei, Aiwen
, p. 4453 - 4456 (2013)
CHoose nickel: The nickel-catalyzed oxidative arylation of C(sp 3)-H bonds has been achieved. Several substituted arylboronic acids and various C(sp3)-H bonds were found to be suitable substrates for this novel transformation, which is likely to proceed through a radical pathway. This method allows the introduction of simple ether derivatives to construct α-arylated ethers. FG=functional group. Copyright
Metal-Free Regioselective Cross Dehydrogenative Coupling of Cyclic Ethers and Aryl Carbonyls
Mane, Kishor D.,Mukherjee, Anagh,Vanka, Kumar,Suryavanshi, Gurunath
, (2019)
A highly regioselective, efficient, and metal-free oxidative cross dehydrogenative coupling (CDC) of aryl carbonyls with cyclic ethers has been developed. This method offers easy access to substituted α-arylated cyclic ethers with a high functional group
Improving the throughput of batch photochemical reactions using flow: Dual photoredox and nickel catalysis in flow for C(sp2)C(sp3) cross-coupling
Abdiaj, Irini,Alcázar, Jesús
supporting information, p. 6190 - 6196 (2017/09/30)
We report herein the transfer of dual photoredox and nickel catalysis for C(sp2)C(sp3) cross coupling form batch to flow. This new procedure clearly improves the scalability of the previous batch reaction by the reactor's size and op
Glycosyl Cross-Coupling of Anomeric Nucleophiles: Scope, Mechanism, and Applications in the Synthesis of Aryl C-Glycosides
Zhu, Feng,Rodriguez, Jacob,Yang, Tianyi,Kevlishvili, Ilia,Miller, Eric,Yi, Duk,O'Neill, Sloane,Rourke, Michael J.,Liu, Peng,Walczak, Maciej A.
supporting information, p. 17908 - 17922 (2017/12/26)
Stereoselective manipulations at the C1 anomeric position of saccharides are one of the central goals of preparative carbohydrate chemistry. Historically, the majority of reactions forming a bond with anomeric carbon has focused on reactions of nucleophiles with saccharide donors equipped with a leaving group. Here, we describe a novel approach to stereoselective synthesis of C-aryl glycosides capitalizing on the highly stereospecific reaction of anomeric nucleophiles. First, methods for the preparation of anomeric stannanes have been developed and optimized to afford both anomers of common saccharides in high anomeric selectivities. We established that oligosaccharide stannanes could be prepared from monosaccharide stannanes via O-glycosylation with Schmidt-type donors, glycal epoxides, or under dehydrative conditions with C1 alcohols. Second, we identified a general set of catalytic conditions with Pd2(dba)3 (2.5 mol%) and a bulky ligand (JackiePhos, 10 mol%) controlling the β-elimination pathway. We demonstrated that the glycosyl cross-coupling resulted in consistently high anomeric selectivities for both anomers with mono- and oligosaccharides, deoxysugars, saccharides with free hydroxyl groups, pyranose, and furanose substrates. The versatility of the glycosyl cross-coupling reaction was probed in the total synthesis of salmochelins (siderophores) and commercial anti-diabetic drugs (gliflozins). Combined experimental and computational studies revealed that the β-elimination pathway is suppressed for biphenyl-type ligands due to the shielding of Pd(II) by sterically demanding JackiePhos, whereas smaller ligands, which allow for the formation of a Pd-F complex, predominantly result in a glycal product. Similar steric effects account for the diminished rates of cross-couplings of 1,2-cis C1-stannanes with aryl halides. DFT calculations also revealed that the transmetalation occurs via a cyclic transition state with retention of configuration at the anomeric position. Taken together, facile access to both anomers of various glycoside nucleophiles, a broad reaction scope, and uniformly high transfer of anomeric configuration make the glycosyl cross-coupling reaction a practical tool for the synthesis of bioactive natural products, drug candidates, allowing for late-stage glycodiversification studies with small molecules and biologics.
Coupling of C(sp3)-H bonds with C(sp2)-O electrophiles: mild, general and selective
Gui, Yong-Yuan,Liao, Li-Li,Sun, Liang,Zhang, Zhen,Ye, Jian-Heng,Shen, Guo,Lu, Zhi-Peng,Zhou, Wen-Jun,Yu, Da-Gang
supporting information, p. 1192 - 1195 (2017/02/05)
Herein is reported the mild and general coupling of amine/ether C(sp3)-H bonds with various kinds of C(sp2)-O electrophiles with high selectivity and efficiency. Valuable allylic/benzylic amines are generated in moderate to excellent yields. The utility of this transformation is demonstrated by a broad substrate scope (>50 examples), good functional group tolerance and facile product modification.
Photochemical Nickel-Catalyzed C-H Arylation: Synthetic Scope and Mechanistic Investigations
Heitz, Drew R.,Tellis, John C.,Molander, Gary A.
supporting information, p. 12715 - 12718 (2016/10/13)
An iridium photocatalyst and visible light facilitate a room temperature, nickel-catalyzed coupling of (hetero)aryl bromides with activated α-heterosubstituted or benzylic C(sp3)-H bonds. Mechanistic investigations on this unprecedented transformation have uncovered the possibility of an unexpected mechanism hypothesized to involve a Ni-Br homolysis event from an excited-state nickel complex. The resultant bromine radical is thought to abstract weak C(sp3)-H bonds to generate reactive alkyl radicals that can be engaged in Ni-catalyzed arylation. Evidence suggests that the iridium photocatalyst facilitates nickel excitation and bromine radical generation via triplet-triplet energy transfer.
Direct C(sp3)-H Cross Coupling Enabled by Catalytic Generation of Chlorine Radicals
Shields, Benjamin J.,Doyle, Abigail G.
supporting information, p. 12719 - 12722 (2016/10/13)
Here we report the development of a C(sp3)-H cross-coupling platform enabled by the catalytic generation of chlorine radicals by nickel and photoredox catalysis. Aryl chlorides serve as both cross-coupling partners and the chlorine radical source for the α-oxy C(sp3)-H arylation of cyclic and acyclic ethers. Mechanistic studies suggest that photolysis of a Ni(III) aryl chloride intermediate, generated by photoredox-mediated single-electron oxidation, leads to elimination of a chlorine radical in what amounts to the sequential capture of two photons. Arylations of a benzylic C(sp3)-H bond of toluene and a completely unactivated C(sp3)-H bond of cyclohexane demonstrate the broad implications of this manifold for accomplishing numerous C(sp3)-H bond functionalizations under exceptionally mild conditions.
Effects of Molecular Oxygen, Solvent, and Light on Iridium-Photoredox/Nickel Dual-Catalyzed Cross-Coupling Reactions
Oderinde, Martins S.,Varela-Alvarez, Adrian,Aquila, Brian,Robbins, Daniel W.,Johannes, Jeffrey W.
supporting information, p. 7642 - 7651 (2015/08/18)
In order to achieve reproducibility during iridium-photoredox and nickel dual-catalyzed sp3-sp2 carbon-carbon bond-forming reactions, we investigated the role that molecular oxygen (O2), solvent and light-source (CF lamp o
DECARBOXYLATIVE CROSS-COUPLING AND APPLICATIONS THEREOF
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Page/Page column 17; 30; 31, (2015/12/09)
Methods described herein enable the production of numerous molecular species through decarboxylative cross-coupling via use of photoredox and transition metal catalysts. For example, methods described herein enable the production of numerous molecular species through decarboxylative cross-coupling via use of photoredox and transition metal catalysts. A method described herein, in some embodiments, comprises providing a reaction mixture including a photoredox catalyst, a transition metal catalyst, a coupling partner and a substrate having a carboxyl group. The reaction mixture is irradiated with a radiation source resulting in cross-coupling of the substrate and coupling partner via a mechanism including decarboxylation, wherein the coupling partner is selected from the group consisting of a substituted aromatic compound and a substituted aliphatic compound.
Merging photoredox with nickel catalysis: Coupling of α-carboxyl sp3-carbons with aryl halides
Zuo, Zhiwei,Ahneman, Derek T.,Chu, Lingling,Terrett, Jack A.,Doyle, Abigail G.,MacMillan, David W. C.
, p. 437 - 440 (2014/08/05)
Over the past 40 years, transition metal catalysis has enabled bond formation between aryl and olefinic (sp2) carbons in a selective and predictable manner with high functional group tolerance. Couplings involving alkyl (sp3) carbons have proven more challenging. Here, we demonstrate that the synergistic combination of photoredox catalysis and nickel catalysis provides an alternative cross-coupling paradigm, in which simple and readily available organic molecules can be systematically used as coupling partners. By using this photoredox-metal catalysis approach, we have achieved a direct decarboxylative sp3-sp2 cross-coupling of amino acids, as well as α-O- or phenyl-substituted carboxylic acids, with aryl halides. Moreover, this mode of catalysis can be applied to direct cross-coupling of Csp3-H in dimethylaniline with aryl halides via C-H functionalization.
