85838-94-4Relevant academic research and scientific papers
Cobalt-Catalyzed C(sp2)-C(sp3) Suzuki-Miyaura Cross-Coupling Enabled by Well-Defined Precatalysts with L,X-Type Ligands
Mills, L. Reginald,Gygi, David,Ludwig, Jacob R.,Simmons, Eric M.,Wisniewski, Steven R.,Kim, Junho,Chirik, Paul J.
, p. 1905 - 1918 (2022/02/07)
Cobalt(II) halides in combination with phenoxyimine (FI) ligands generated efficient precatalysts in situ for the C(sp2)-C(sp3) Suzuki-Miyaura cross-coupling between alkyl bromides and neopentylglycol (hetero)arylboronic esters. The protocol enabled efficient C-C bond formation with a host of nucleophiles and electrophiles (36 examples, 34-95%) with precatalyst loadings of 5 mol %. Studies with alkyl halide electrophiles that function as radical clocks support the intermediacy of alkyl radicals during the course of the catalytic reaction. The improved performance of the FI-cobalt catalyst was correlated with decreased lifetimes of cage-escaped radicals as compared to those of diamine-type ligands. Studies of the phenoxyimine-cobalt coordination chemistry validate the L,X interaction leading to the discovery of an optimal, well-defined, air-stable mono-FI-cobalt(II) precatalyst structure.
A general N-alkylation platform via copper metallaphotoredox and silyl radical activation of alkyl halides
Cabré, Albert,Dow, Nathan W.,MacMillan, David W. C.
supporting information, p. 1827 - 1842 (2021/07/07)
The catalytic union of amides, sulfonamides, anilines, imines, or N-heterocycles with a broad spectrum of electronically and sterically diverse alkyl bromides has been achieved via a visible-light-induced metallaphotoredox platform. The use of a halogen abstraction-radical capture (HARC) mechanism allows for room temperature coupling of C(sp3)-bromides using simple Cu(II) salts, effectively bypassing the prohibitively high barriers typically associated with thermally induced SN2 or SN1 N-alkylation. This regio- and chemoselective protocol is compatible with >10 classes of medicinally relevant N-nucleophiles, including established pharmaceutical agents, in addition to structurally diverse primary, secondary, and tertiary alkyl bromides. Furthermore, the capacity of HARC methodologies to engage conventionally inert coupling partners is highlighted via the union of N-nucleophiles with cyclopropyl bromides and unactivated alkyl chlorides, substrates that are incompatible with nucleophilic substitution pathways. Preliminary mechanistic experiments validate the dual catalytic, open-shell nature of this platform, which enables reactivity previously unattainable in traditional halide-based N-alkylation systems.
Merging Halogen-Atom Transfer (XAT) and Cobalt Catalysis to Override E2-Selectivity in the Elimination of Alkyl Halides: A Mild Route towardcontra-Thermodynamic Olefins
Zhao, Huaibo,McMillan, Alastair J.,Constantin, Timothée,Mykura, Rory C.,Juliá, Fabio,Leonori, Daniele
supporting information, p. 14806 - 14813 (2021/09/18)
We report here a mechanistically distinct tactic to carry E2-type eliminations on alkyl halides. This strategy exploits the interplay of α-aminoalkyl radical-mediated halogen-atom transfer (XAT) with desaturative cobalt catalysis. The methodology is high-yielding, tolerates many functionalities, and was used to access industrially relevant materials. In contrast to thermal E2 eliminations where unsymmetrical substrates give regioisomeric mixtures, this approach enables, by fine-tuning of the electronic and steric properties of the cobalt catalyst, to obtain high olefin positional selectivity. This unprecedented mechanistic feature has allowed access tocontra-thermodynamic olefins, elusive by E2 eliminations.
Nickel-Catalyzed Formal Aminocarbonylation of Unactivated Alkyl Iodides with Isocyanides
Chen, Yifeng,Huang, Wenyi,Qu, Jingping,Shrestha, Mohini,Wang, Yun,Weng, Yangyang
supporting information, p. 3245 - 3250 (2020/04/21)
Herein, we disclose a Ni-catalyzed formal aminocarbonylation of primary and secondary unactivated aliphatic iodides with isocyanides to afford alkyl amide, which proceeds via the selective monomigratory insertion of isocyanides with alkyl iodides, subsequent β-hydride elimination, and hydrolysis process. The reaction features wide functional group tolerance under mild conditions. Additionally, the selective, one-pot hydrolysis of reaction mixture under acid conditions allows for expedient synthesis of the corresponding alkyl carboxylic acid.
Copper-Catalyzed Cross-Coupling between Alkyl (Pseudo)halides and Bicyclopentyl Grignard Reagents
Andersen, Claire,Bernardelli, Patrick,Cossy, Janine,Daumas, Marc,Ferey, Vincent,Guérinot, Amandine
, (2020/08/05)
The development of a copper-catalyzed cross-coupling between primary and secondary (pseudo)halides and bicyclopentyl Grignard reagents is reported. Highly strained bicyclopentanes can be cross-coupled with a large panel of primary alkyl mesylates and secondary alkyl iodides. The catalytic system is simple and cheap, and the reaction is general and chemoselective.
Palladium-Catalyzed Visible-Light-Driven Carboxylation of Aryl and Alkenyl Triflates by Using Photoredox Catalysts
Shimomaki, Katsuya,Nakajima, Tomoya,Caner, Joaquim,Toriumi, Naoyuki,Iwasawa, Nobuharu
supporting information, p. 4486 - 4489 (2019/06/24)
A visible-light-driven carboxylation of aryl and alkenyl triflates with CO2 is developed by using a combination of Pd and photoredox catalysts. This reaction proceeds under mild conditions and can be applied to a wide range of substrates including acyclic alkenyl triflates.
Synthesis, molecular modeling and evaluation of α-glucosidase inhibition activity of 3,4-dihydroxy piperidines
Kasturi, Siva Prasad,Surarapu, Sujatha,Uppalanchi, Srinivas,Dwivedi, Shubham,Yogeeswari, Perumal,Sigalapalli, Dilep Kumar,Bathini, Nagendra Babu,Ethiraj, Krishna S.,Anireddy, Jaya Shree
, p. 39 - 52 (2018/03/09)
Biological evaluation of 3,4-dihydroxy piperidines as α-glucosidase inhibitors is being reported for the first time. Forty-five derivatives (amides, di-amides and sulfonamides) were made using cis and trans 3,4-dihydroxy piperidines to evaluate their α-glucosidase inhibition activity. Polar groups (-OH, -NH2) on phenyl ring having derivatives 5i, 5l, 7g, 7i & 12j showed excellent activity compared to standard references. Acarbose, Voglibose and Miglitol were used as standard references. Molecular docking simulations were done for compounds to identify important binding modes responsible for inhibition activity of α-glucosidase.
Method for preparing N-substituted-1,2,3,6-tetrahydropyridine
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Paragraph 0023; 0024; 0025; 0026; 0030, (2018/05/16)
The invention discloses a method for preparing N-substituted-1,2,3,6-tetrahydropyridine and belongs to the technical field of organic chemistry. N-substituted-4-piperidinol as a raw material reacts with triphenylphosphine and azodicarbonic acid diester, alcoholic hydroxyl groups are converted into alkenyl groups, and N-substituted-1,2,3,6-tetrahydropyridine is prepared. The method has the advantages that the raw materials are easily available, the operation is simple and convenient, the product purity is high, demands of the conventional method for high-temperature condition and highly toxic chemicals are avoided, and the method has potential route advantage.
Saturated Heterocyclic Aminosulfonyl Fluorides: New Scaffolds for Protecting-Group-Free Synthesis of Sulfonamides
Zhersh, Sergey A.,Blahun, Oleksandr P.,Sadkova, Iryna V.,Tolmachev, Andrey A.,Moroz, Yurii S.,Mykhailiuk, Pavel K.
supporting information, p. 8343 - 8349 (2018/06/04)
Cyclic saturated aminosulfonyl fluorides were synthesized as their HCl salts. The compounds were found to be stable upon storage and could be used for the protecting-group-free synthesis of sulfonamides. In the presence of the ?SO2F group, the nitrogen atom could be modified by means of acylation, arylation, or reductive amination to give products that have high potential for the synthesis of bioactive compounds.
A N - Boc - 4 - piperidine formaldehyde preparation method (by machine translation)
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Paragraph 0023-0024, (2018/03/26)
The invention discloses a N - Boc - 4 - piperidine formaldehyde preparation method, which belongs to the technical field of organic chemistry. From the N - Boc - 4 - piperidone as the starting point, and the toluene shPs reaction generating diethylketohydrazone, then add the butyl lithium/tetramethyl ethylenediamine/formylation reagent reaction to obtain the 1 - Boc - 4 - formyl - 3, 6 - dihydro - 2 H - pyridine, then palladium carbon to catalyze hydrogenation to obtain N - Boc - 4 - piperidine formaldehyde. The invention has simple operation, higher yield, use of the starting raw material is cheap, is preparing N - Boc - 4 - piperidine formaldehyde suitable method. (by machine translation)
