325142-89-0Relevant articles and documents
Mono-Phosphine Metal-Organic Framework-Supported Cobalt Catalyst for Efficient Borylation Reactions
Akhtar, Naved,Antil, Neha,Balendra,Begum, Wahida,Chauhan, Manav,Gupta, Poorvi,Kumar, Ajay,Malik, Jaideep,Manna, Kuntal,Newar, Rajashree
supporting information, (2022/03/15)
We report a metal-organic framework (MOF) supported monoligated phosphine-cobalt complex, which is an active heterogeneous catalyst for aromatic C?H borylation and alkene hydroboration. The mono(phosphine)-Co catalyst (MOF?P?Co) was prepared by metalation of a porous triarylphosphine-functionalized MOF (MOF?P) with CoCl2 followed by activation with NaEt3BH. The MOF catalyst has a broad substrate scope with excellent functional group tolerance to afford arene- and alkyl-boronate esters in excellent yields and selectivity. MOF?P?Co gave a turnover number (TON) of 30,000 and could be recycled and reused at least 13 times in arene C?H borylation. Importantly, the attempt to prepare the homogeneous control (Ph3P?Co) using triphenylphosphine was unsuccessful due to the facile disproportionation reactions or intermolecular ligand exchanges in the solution. In contrast, the site isolation of the active mono(phosphine)-Co species within the MOF affords the robust and coordinatively unsaturated metal complexes, allowing to explore their catalytic properties and the reaction mechanism.
Remote steric control for undirected meta-selective C-H activation of arenes
Asako, Sobi,Ilies, Laurean,Jin, Yushu,Ramadoss, Boobalan
, p. 658 - 663 (2022/02/21)
Regioselective functionalization of arenes remains a challenging problem in organic synthesis. Steric interactions are often used to block sites adjacent to a given substituent, but they do not distinguish the remaining remote sites. We report a strategy
Development of Potent PfCLK3 Inhibitors Based on TCMDC-135051 as a New Class of Antimalarials
Mahindra, Amit,Janha, Omar,Mapesa, Kopano,Sanchez-Azqueta, Ana,Alam, Mahmood M.,Amambua-Ngwa, Alfred,Nwakanma, Davis C.,Tobin, Andrew B.,Jamieson, Andrew G.
supporting information, p. 9300 - 9315 (2020/10/19)
The protein kinase PfCLK3 plays a critical role in the regulation of malarial parasite RNA splicing and is essential for the survival of blood stage Plasmodium falciparum. We recently validated PfCLK3 as a drug target in malaria that offers prophylactic,
Iron-Catalyzed Borylation of Aryl Ethers via Cleavage of C-O Bonds
Zeng, Xiaoqin,Zhang, Yuxuan,Liu, Zhengli,Geng, Shasha,He, Yun,Feng, Zhang
, p. 2950 - 2955 (2020/04/15)
Herein, we report the iron-catalyzed borylation of aryl ethers and aryl amines via cleavage of C-O and C-N bonds. This protocol does not require the use of Grignard reagents and displays a broad substrate scope, which allows the late-stage borylation. It also provides facile access to multisubstituted arenes through C-H functionalization using 2-pyridyloxy as the directing group.
Nickel-Catalyzed C(sp2)-H Borylation of Arenes
Das, Arpan,Hota, Pradip Kumar,Mandal, Swadhin K.
, (2019/09/12)
In this study, C(sp2)-H borylation of arenes was accomplished by a nickel catalyst, resulting in good yield. Alkyl and alkoxy arenes were successfully functionalized, affording C(sp2)-H borylated compounds. It was unraveled that the well-defined abnormal N-heterocyclic carbene based Ni(II) complex breaks into Ni nanoparticles (Ni-NPs), which act as catalytically active species. A series of controlled reactions under stoichiometric conditions along with spectroscopic studies and single-crystal X-ray crystallographic study helped us to understand the formation of Ni-NPs along with formation of a boron(III) compound during this reaction.
Iron-catalyzed C-H borylation of arenes
Dombray, Thomas,Werncke, C. Gunnar,Jiang, Shi,Grellier, Mary,Vendier, Laure,Bontemps, Sébastien,Sortais, Jean-Baptiste,Sabo-Etienne, Sylviane,Darcel, Christophe
supporting information, p. 4062 - 4065 (2015/04/14)
Well-defined iron bis(diphosphine) complexes are active catalysts for the dehydrogenative C-H borylation of aromatic and heteroaromatic derivatives with pinacolborane. The corresponding borylated compounds were isolated in moderate to good yields (25-73%) with a 5 mol% catalyst loading under UV irradiation (350 nm) at room temperature. Stoichiometric reactivity studies and isolation of an original trans-hydrido(boryl)iron complex, Fe(H)(Bpin)(dmpe)2, allowed us to propose a mechanism showing the role of some key catalytic species.
Efficient Rh-catalyzed C-H borylation of arene derivatives under photochemical conditions
Bheeter, Charles Beromeo,Chowdhury, Abhishek Dutta,Adam, Rosa,Jackstell, Ralf,Beller, Matthias
supporting information, p. 10336 - 10340 (2015/10/28)
Photocatalysis allows innovations in organic synthesis. Among the various catalytic reactions, CH-functionalizations offer valuable possibilities for the refinement of easily available building blocks. In this respect, catalytic borylation is of interest, too. So far, most of the catalytic borylation reactions are performed under thermal conditions at comparably high temperatures. Here, we describe a new synthetic route for efficient borylation reactions of arenes using a photocatalytic pathway. This novel approach allows the synthesis of a broad variety of borylated arenes and heteroarenes under mild conditions. Applying trans-[Rh(PMe3)2(CO)Cl] as an active photocatalyst and HBPin as an boron source, we achieved high TON. A catalytic cycle that relies on a Rh(i)-Rh(iii) interconversion is proposed.
Para -C-H borylation of benzene derivatives by a bulky iridium catalyst
Saito, Yutaro,Segawa, Yasutomo,Itami, Kenichiro
supporting information, p. 5193 - 5198 (2015/05/05)
A highly para-selective aromatic C-H borylation has been accomplished. By a new iridium catalyst bearing a bulky diphosphine ligand, Xyl-MeO-BIPHEP, the C-H borylation of monosubstituted benzenes can be affected with para-selectivity up to 91%. This catalytic system is quite different from the usual iridium catalysts that cannot distinguish meta- and para-C-H bonds of monosubstituted benzene derivatives, resulting in the preferred formation of meta-products. The para-selectivity increases with increasing bulkiness of the substituent on the arene, indicating that the regioselectivity of the present reaction is primarily controlled by steric repulsion between substrate and catalyst. Caramiphen, an anticholinergic drug used in the treatment of Parkinsons disease, was converted into five derivatives via our para-selective borylation. The present [Ir(cod)OH]2/Xyl-MeO-BIPHEP catalyst represents a unique, sterically controlled, para-selective, aromatic C-H borylation system that should find use in streamlined, predictable chemical synthesis and in the rapid discovery and optimization of pharmaceuticals and materials.
A modular synthesis of teraryl-based α-helix mimetics, part 1: Synthesis of core fragments with two electronically differentiated leaving groups
Peters, Martin,Trobe, Melanie,Tan, Hao,Kleineweischede, Rolf,Breinbauer, Rolf
supporting information, p. 2442 - 2449 (2013/04/24)
Teraryl-based α-helix mimetics have proven to be useful compounds for the inhibition of protein-protein interactions (PPI). We have developed a modular and flexible approach for the synthesis of teraryl-based α-helix mimetics. Central to our strategy is the use of a benzene core unit featuring two leaving groups of differentiated reactivity in the Pd-catalyzed cross-coupling used for terphenyl assembly. With the halogen/diazonium route and the halogen/triflate route, two strategies have successfully been established. The synthesis of core building blocks with aliphatic (Ala, Val, Leu, Ile), aromatic (Phe), polar (Cys, Lys), hydrophilic (Ser, Gln), and acidic (Glu) amino acid side chains are reported. Turn on: Teraryl-based α-helix mimetics can be effectively produced by sequential Suzuki coupling of a central core fragment featuring electronically differentiated leaving groups with aryl boronic pinacol esters (see scheme; dppf=1,1′-bis(diphenylphosphino) ferrocene, DME=dimethoxyethane, Pin=pinacol, Tf=trifluoromethanesulfonyl). With a set of only 2×18 building blocks, all permutations of α-helix mimetics can be produced. Copyright
Substituted imidazol-pyridazine derivatives
-
Page 18, (2010/02/05)
The present invention relates to compounds of formula wherein A is an unsubstituted or substituted cyclic group; and R is hydrogen or lower alkyl; or a pharmaceutically acceptable acid addition salt thereof. These compounds are NMDA NR-2B receptor subtype specific blockers and are useful in the treatment of neurodegeneration, depression and pain.
