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Emayavaramban B, Chakraborty P, Sundararaju B. Cobalt-Catalyzed Reductive Alkylation of Amines with Carboxylic Acids. CHEMSUSCHEM 2019; 12:3089-3093. [PMID: 30418691 DOI: 10.1002/cssc.201802144] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Direct reductive alkylation of amines with carboxylic acid is carried out by using an inexpensive, air-stable cobalt/triphos catalytic system with molecular hydrogen as the reductant. This efficient synthetic method proceeds through reduction and condensation, followed by reduction of the in situ-generated imine into the amine in a green catalytic process.
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Emayavaramban B, Chakraborty P, Manoury E, Poli R, Sundararaju B. Cp*Co(iii)-catalyzed N-alkylation of amines with secondary alcohols. Org Chem Front 2019. [DOI: 10.1039/c8qo01389f] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We report here the first high-valent cobalt(iii)-catalyzed direct alkylation of aromatic amines with secondary alcohols.
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Kalsi D, Barsu N, Chakrabarti S, Dahiya P, Rueping M, Sundararaju B. C–H and N–H bond annulation of aryl amides with unactivated olefins by merging cobalt(iii) and photoredox catalysis. Chem Commun (Camb) 2019; 55:11626-11629. [DOI: 10.1039/c9cc05744g] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A mild, environment-friendly protocol has been developed to carry out the [4+2] annulation of aryl amides with unactivated olefins.
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Gangwar MK, Dahiya P, Emayavaramban B, Sundararaju B. Cp*Co III -Catalyzed Efficient Dehydrogenation of Secondary Alcohols. Chem Asian J 2018; 13:2445-2448. [PMID: 29863804 DOI: 10.1002/asia.201800697] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 06/01/2018] [Indexed: 11/09/2022]
Abstract
A novel, well-defined molecular Cp*CoIII complex was isolated and structurally characterized for the first time. The efficiency of this cobalt catalyst was demonstrated in the alcohol dehydrogenation and dehydrative coupling of secondary alcohols under mild conditions into ketones and ethers, respectively.
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Kalsi D, Dutta S, Barsu N, Rueping M, Sundararaju B. Room-Temperature C–H Bond Functionalization by Merging Cobalt and Photoredox Catalysis. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02118] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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31
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Rajesh N, Sundararaju B. Nickel-catalyzed C−H bond Alkoxylation of Amides with Alcohols. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800286] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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32
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Mandal R, Emayavaramban B, Sundararaju B. Cp*Co(III)-Catalyzed C–H Alkylation with Maleimides Using Weakly Coordinating Carbonyl Directing Groups. Org Lett 2018; 20:2835-2838. [DOI: 10.1021/acs.orglett.8b00761] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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33
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Kalsi D, Barsu N, Sundararaju B. CoIII
-Catalyzed Isonitrile Insertion/Acyl Group Migration Between C−H and N−H bonds of Arylamides. Chemistry 2018; 24:2360-2364. [DOI: 10.1002/chem.201705710] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Indexed: 11/09/2022]
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34
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Barsu N, Kalsi D, Sundararaju B. Site-selective C–H bond carbonylation with CO2 and cobalt-catalysis. Catal Sci Technol 2018. [DOI: 10.1039/c8cy02060d] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Utilization of anthropogenic greenhouse gas CO2 for catalytic C–C bond formation via conversion to essentially valuable C1 synthons like CO is very challenging.
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Sen M, Rajesh N, Emayavaramban B, Premkumar JR, Sundararaju B. Isolation of Cp*Co III -Alkenyl Intermediate in Efficient Cobalt-Catalyzed C-H Alkenylation with Alkynes. Chemistry 2017; 24:342-346. [PMID: 29164708 DOI: 10.1002/chem.201705183] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Indexed: 11/07/2022]
Abstract
A general and efficient procedure for C-H alkenylation of arenes with a broad substrate scope catalyzed by Cp*CoIII was demonstrated with alkynes. A highly selective mono-alkenylation and sequential bis-C-H bond functionalization was displayed to exemplify the versatility of the cobalt catalyst. Isolation of cationic Cp*CoIII -alkenyl intermediate was achieved under identical catalytic conditions to further establish the proposed pathway.
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Sen M, Mandal R, Das A, Kalsi D, Sundararaju B. Cp*CoIII
-Catalyzed Bis-isoquinolone Synthesis by C−H Annulation of Arylamide with 1,3-Diyne. Chemistry 2017; 23:17454-17457. [DOI: 10.1002/chem.201704155] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Indexed: 12/27/2022]
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37
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Barsu N, Emayavaramban B, Sundararaju B. Linear Selective C-H Bond Alkylation with Activated Olefins Catalyzed by Cp*CoIII. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700696] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Sen M, Dahiya P, Premkumar JR, Sundararaju B. Dehydrative Cp*Co(III)-Catalyzed C–H Bond Allenylation. Org Lett 2017; 19:3699-3702. [DOI: 10.1021/acs.orglett.7b01415] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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39
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Kalsi D, Barsu N, Dahiya P, Sundararaju B. C–H and N–H Bond Annulation of Benzamides with Isonitriles Catalyzed by Cobalt(III). SYNTHESIS-STUTTGART 2017. [DOI: 10.1055/s-0036-1589011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
A simple efficient, atom-economical procedure was developed for the cobalt-catalyzed C–H bond annulation of benzamides with isonitriles under mild conditions. The reaction tolerates a variety of functional group including heterocycles. Diverse 3-(alkylimino)-2-quinolin-8-yl-2,3-dihydro-1H-isoindol-1-ones were synthesized using isonitriles as the C1 source through C–H and N–H bond annulation via C–H bond activation in a ‘green’ solvent. Vinylamides were also used similarly with tert-butyl isonitrile to give 3-(tert-butylimino)-1-quinolin-8-yl-1H-pyrrol-2(5H)-ones.
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Abstract
A new procedure for oxidative coupling of aromatic and acrylic acids with alkynes has been developed using abundant, nontoxic, and air stable Cp*Co(III) catalyst. The coupling involves initial cyclometalation via weak chelation-assisted C-H bond activation followed by alkyne coordination, insertion, and reductive elimination leading to diverse isocoumarins (α-pyranones) in good yields under mild conditions.
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Barsu N, Bolli SK, Sundararaju B. Cobalt catalyzed carbonylation of unactivated C(sp 3)-H bonds. Chem Sci 2017; 8:2431-2435. [PMID: 28451350 PMCID: PMC5369400 DOI: 10.1039/c6sc05026c] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 12/19/2016] [Indexed: 12/23/2022] Open
Abstract
A general efficient regioselective cobalt catalyzed carbonylation of unactivated C(sp3)-H bonds of aliphatic amides was demonstrated using atmospheric (1-2 atm) carbon monoxide as a C1 source. This straightforward approach provides access to α-spiral succinimide regioselectively in a good yield. Cobalt catalyzed sp3 C-H bond carbonylation is reported for the first time including the functionalization of (β)-C-H bonds of α-1°, 2°, 3° carbons and even internal (β)-C-H bonds. Our initial mechanistic investigation reveals that the C-H activation step is irreversible and will possibly be the rate determining step.
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Kalsi D, Laskar RA, Barsu N, Premkumar JR, Sundararaju B. C-8-Selective Allylation of Quinoline: A Case Study of β-Hydride vs β-Hydroxy Elimination. Org Lett 2016; 18:4198-201. [DOI: 10.1021/acs.orglett.6b01845] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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44
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Barsu N, Rahman MA, Sen M, Sundararaju B. Cp*CoIII-Catalyzed C(sp3)−H Bond Amidation of 8-Methylquinoline. Chemistry 2016; 22:9135-8. [DOI: 10.1002/chem.201601597] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Indexed: 01/05/2023]
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45
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Sen M, Emayavaramban B, Barsu N, Premkumar JR, Sundararaju B. Cp*Co(III)-Catalyzed C(sp3)–H Bond Activation: A Highly Stereoselective and Regioselective Alkenylation of 8-Methylquinoline with Alkynes. ACS Catal 2016. [DOI: 10.1021/acscatal.6b00612] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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46
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Emayavaramban B, Roy M, Sundararaju B. Iron-Catalyzed Allylic Amination Directly from Allylic Alcohols. Chemistry 2016; 22:3952-5. [PMID: 26812622 DOI: 10.1002/chem.201505214] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Indexed: 11/07/2022]
Abstract
Allylic amination, directly from alcohols, has been demonstrated without any Lewis acid activators using an efficient and regiospecific molecular iron catalyst. Various amines and alcohols were employed and the reaction proceeded through the oxidation/reduction (redox) pathway. A direct one-step synthesis of common drugs, such as cinnarizine and nafetifine, was exhibited from cinnamyl alcohol that produced water as side product.
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Barsu N, Sen M, Premkumar JR, Sundararaju B. Cobalt(iii) catalyzed C-8 selective C–H and C–O coupling of quinoline N-oxide with internal alkynes via C–H activation and oxygen atom transfer. Chem Commun (Camb) 2016; 52:1338-41. [DOI: 10.1039/c5cc08736h] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An efficient, scalable, atom-economical, regio-selective air stable Cp*Co(iii) catalyzed C–H and C–O coupling via a C–H activation/oxygen atom transfer reaction of quinoline N-oxide and an internal alkyne is reported.
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Kalsi D, Sundararaju B. Cobalt Catalyzed C–H and N–H Bond Annulation of Sulfonamide with Terminal and Internal Alkynes. Org Lett 2015; 17:6118-21. [DOI: 10.1021/acs.orglett.5b03142] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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49
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Sen M, Kalsi D, Sundararaju B. Cobalt(III)-Catalyzed Dehydrative [4+2] Annulation of Oxime with Alkyne by CH and NOH Activation. Chemistry 2015; 21:15529-33. [DOI: 10.1002/chem.201503643] [Citation(s) in RCA: 172] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/11/2015] [Indexed: 02/02/2023]
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50
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Barsu N, Kalsi D, Sundararaju B. Carboxylate Assisted Ni-Catalyzed CH Bond Allylation of Benzamides. Chemistry 2015; 21:9364-8. [DOI: 10.1002/chem.201500639] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Indexed: 11/06/2022]
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