1
|
Ansari MF, Maurya AK, Kumar A, Elangovan S. Manganese-catalyzed C-C and C-N bond formation with alcohols via borrowing hydrogen or hydrogen auto-transfer. Beilstein J Org Chem 2024; 20:1111-1166. [PMID: 38887586 PMCID: PMC11181258 DOI: 10.3762/bjoc.20.98] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 04/24/2024] [Indexed: 06/20/2024] Open
Abstract
Transition-metal-mediated "borrowing hydrogen" also known as hydrogen auto-transfer reactions allow the sustainable construction of C-C and C-N bonds using alcohols as hydrogen donors. In recent years, manganese complexes have been explored as efficient catalysts in these reactions. This review highlights the significant progress made in manganese-catalyzed C-C and C-N bond-formation reactions via hydrogen auto-transfer, emphasizing the importance of this methodology and manganese catalysts in sustainable synthesis strategies.
Collapse
Affiliation(s)
- Mohd Farhan Ansari
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Atul Kumar Maurya
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Abhishek Kumar
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Saravanakumar Elangovan
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| |
Collapse
|
2
|
Bera S, Kabadwal LM, Banerjee D. Harnessing alcohols as sustainable reagents for late-stage functionalisation: synthesis of drugs and bio-inspired compounds. Chem Soc Rev 2024; 53:4607-4647. [PMID: 38525675 DOI: 10.1039/d3cs00942d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Alcohol is ubiquitous with unparalleled structural diversity and thus has wide applications as a native functional group in organic synthesis. It is highly prevalent among biomolecules and offers promising opportunities for the development of chemical libraries. Over the last decade, alcohol has been extensively used as an environmentally friendly chemical for numerous organic transformations. In this review, we collectively discuss the utilisation of alcohol from 2015 to 2023 in various organic transformations and their application toward intermediates of drugs, drug derivatives and natural product-like molecules. Notable features discussed are as follows: (i) sustainable approaches for C-X alkylation (X = C, N, or O) including O-phosphorylation of alcohols, (ii) newer strategies using methanol as a methylating reagent, (iii) allylation of alkenes and alkynes including allylic trifluoromethylations, (iv) alkenylation of N-heterocycles, ketones, sulfones, and ylides towards the synthesis of drug-like molecules, (v) cyclisation and annulation to pharmaceutically active molecules, and (vi) coupling of alcohols with aryl halides or triflates, aryl cyanide and olefins to access drug-like molecules. We summarise the synthesis of over 100 drugs via several approaches, where alcohol was used as one of the potential coupling partners. Additionally, a library of molecules consisting over 60 fatty acids or steroid motifs is documented for late-stage functionalisation including the challenges and opportunities for harnessing alcohols as renewable resources.
Collapse
Affiliation(s)
- Sourajit Bera
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Lalit Mohan Kabadwal
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Debasis Banerjee
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| |
Collapse
|
3
|
Mondal A, Phukan HJ, Pal D, Kumar S, Roy M, Srimani D. Well-Defined Mn(II)-complex Catalyzed Switchable De(hydrogenative) Csp 3 -H Functionalization of Methyl Heteroarenes: A Sustainable Approach for Diversification of Heterocyclic Motifs. Chemistry 2024; 30:e202303315. [PMID: 37933814 DOI: 10.1002/chem.202303315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/08/2023]
Abstract
Catalytic activities of Mn(I) complexes derived from expensive MnBr(CO)5 salt have been explored in various dehydrogenative transformations. However, the reactivity and selectivity of inexpensive high spin Mn(II) complexes are uncommon. Herein, we have synthesized four new Mn(II) complexes and explored switchable alkenylation and alkylation of methyl heteroarenes employing a single Mn(II)catalyst. The developed protocol selectively furnishes a series of functionalized E-heteroarenes and C-alkylated heteroarenes with good to excellent yields. Various medicinally and synthetically useful compounds are successfully synthesized using our developed protocol. Various controls and kinetics experiments were executed to shed light on the mechaism,which reveals that α-C-H bond breaking of alcohol is the slowest step.
Collapse
Affiliation(s)
- Avijit Mondal
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| | - Hirak Jyoti Phukan
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| | - Debjyoti Pal
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| | - Saurabh Kumar
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| | - Mithu Roy
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| | - Dipankar Srimani
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam, 781039, India
| |
Collapse
|
4
|
Jalwal S, Regina A, Atreya V, Paranjothy M, Chakraborty S. NNN manganese complex-catalyzed α-alkylation of methyl ketones using alcohols: an experimental and computational study. Dalton Trans 2024. [PMID: 38251673 DOI: 10.1039/d3dt04321e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
We present here a phosphine-free, quinoline-based pincer Mn catalyst for α-alkylation of methyl ketones using primary alcohols as alkyl surrogates. The C-C bond formation reaction proceeds via a hydrogen auto-transfer methodology. The sole by-product formed is water, rendering the protocol atom efficient. Electronic structure theory studies corroborated the proposed mechanism.
Collapse
Affiliation(s)
- Sachin Jalwal
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Anitta Regina
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Vaishnavi Atreya
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Manikandan Paranjothy
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Subrata Chakraborty
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| |
Collapse
|
5
|
Babu R, Sukanya Padhy S, Kumar R, Balaraman E. Catalytic Amination of Alcohols Using Diazo Compounds under Manganese Catalysis Through Hydrogenative N-Alkylation Reaction. Chemistry 2023; 29:e202302007. [PMID: 37486329 DOI: 10.1002/chem.202302007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/25/2023]
Abstract
Sustainable chemical production requires fundamentally new types of catalysts and catalytic technologies. The development of coherent and robust catalytic systems based on earth-abundant transition metals is essential, but highly challenging. Herein, we systematically explored a general hydrogenative cleavage/N-alkylation tandem of cyclic and acyclic diazo (N=N) compounds to value-added amines under manganese catalysis. The reaction is catalyzed by a single-site molecular manganese complex and proceeds via tandem dehydrogenation, transfer hydrogenation, and borrowing hydrogenation strategies. Interestingly, the reaction involves abundantly available renewable feedstocks, such as alcohols, that can act as (transfer)hydrogenating and alkylating agents. The synthetic application of our approach in large-scale pharmaceutical synthesis and easy access to highly demanding N-CH3 /CD3 derivatives are also demonstrated. Kinetic studies show that the reaction rate depends on the concentration of alcohol and Mn-catalyst and follows fractional orders. Several selective bond activation/formation reactions occur sequentially via amine-amide metal-ligand cooperation.
Collapse
Affiliation(s)
- Reshma Babu
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, 517507, Andhra Pradesh, India
| | - Subarna Sukanya Padhy
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, 517507, Andhra Pradesh, India
| | - Rohit Kumar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, 517507, Andhra Pradesh, India
| | - Ekambaram Balaraman
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, 517507, Andhra Pradesh, India
| |
Collapse
|
6
|
Jana A, Chakraborty S, Sarkar K, Maji B. Ruthenium-Catalyzed Reductive Coupling of Epoxides with Primary Alcohols via Hydrogen Transfer Catalysis. J Org Chem 2023; 88:310-318. [PMID: 36546672 DOI: 10.1021/acs.joc.2c02354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Herein, we report the ruthenium-catalyzed synthesis of β-alkylated secondary alcohols via the regioselective ring-opening of epoxides with feedstock primary alcohols. The reaction utilized alcohol as the carbon source and the terminal reductant. Kinetic and labeling experiments elucidate the hydrogen transfer catalysis that operates via tandem Markovnikov selective transfer hydrogenation of terminal epoxides and hydrogen transfer-mediated cross-coupling of the resulting alcohol with primary alcohol substrates. A broad scope (40 examples including drugs/natural product derivatives) and excellent regioselectivity for a variety of substrates were shown.
Collapse
Affiliation(s)
- Akash Jana
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Sayandip Chakraborty
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Koushik Sarkar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Biplab Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| |
Collapse
|
7
|
Liu X, Sotiropoulos J, Taillefer M. A New Route to
E
‐Stilbenes through the Transition‐Metal‐Free KO
t
Bu/DMF‐Promoted Direct Coupling of Alcohols with Phenyl Acetonitriles. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xiaoping Liu
- ICGM Université de Montpellier, <orgDiv/CNRS, ENSCM 34296 Montpellier France
| | | | - Marc Taillefer
- ICGM Université de Montpellier, <orgDiv/CNRS, ENSCM 34296 Montpellier France
| |
Collapse
|
8
|
Das K, Waiba S, Jana A, Maji B. Manganese-catalyzed hydrogenation, dehydrogenation, and hydroelementation reactions. Chem Soc Rev 2022; 51:4386-4464. [PMID: 35583150 DOI: 10.1039/d2cs00093h] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The emerging field of organometallic catalysis has shifted towards research on Earth-abundant transition metals due to their ready availability, economic advantage, and novel properties. In this case, manganese, the third most abundant transition-metal in the Earth's crust, has emerged as one of the leading competitors. Accordingly, a large number of molecularly-defined Mn-complexes has been synthesized and employed for hydrogenation, dehydrogenation, and hydroelementation reactions. In this regard, catalyst design is based on three pillars, namely, metal-ligand bifunctionality, ligand hemilability, and redox activity. Indeed, the developed catalysts not only differ in the number of chelating atoms they possess but also their working principles, thereby leading to different turnover numbers for product molecules. Hence, the critical assessment of molecularly defined manganese catalysts in terms of chelating atoms, reaction conditions, mechanistic pathway, and product turnover number is significant. Herein, we analyze manganese complexes for their catalytic activity, versatility to allow multiple transformations and their routes to convert substrates to target molecules. This article will also be helpful to get significant insight into ligand design, thereby aiding catalysis design.
Collapse
Affiliation(s)
- Kuhali Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Satyadeep Waiba
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Akash Jana
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Biplab Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| |
Collapse
|
9
|
Patra K, Laskar RA, Nath A, Bera JK. A Protic Mn(I) Complex Based on a Naphthyridine- N-oxide Scaffold: Protonation/Deprotonation Studies and Catalytic Applications for Alkylation of Ketones. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00085] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Kamaless Patra
- Department of Chemistry and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Roshayed Ali Laskar
- Department of Chemistry and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Anubhav Nath
- Department of Chemistry and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Jitendra K. Bera
- Department of Chemistry and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| |
Collapse
|
10
|
Pawar G, Ghouse SM, Kar S, Chelli SM, Dannarm SR, Gour J, Sonti R, Nanduri S. SmI2-mediated C-alkylation of Ketones with Alcohols in Microwave conditions: A Novel Route to Alkylated Ketones. Chem Asian J 2022; 17:e202200041. [PMID: 35191612 DOI: 10.1002/asia.202200041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/15/2022] [Indexed: 11/08/2022]
Abstract
A novel protocol is developed towards the preparation of alkylated ketones from alcohols in presence of catalytic amount of SmI 2 and base with the elimination of water as a single by-product under microwave irradiation conditions. Furthermore, applicability of this methodology to the synthesis of Donepezil and late-stage functionalization in Pregnenolone is also reported. Successful application of this methodology in Friedländer quinolone synthesis using 2-aminobenzyl alcohol and various acetophenones expand the synthetic utility of this protocol.
Collapse
Affiliation(s)
- Gaurav Pawar
- NIPER Hyderabad: National Institute of Pharmaceutical Education and Research Hyderabad, Chemical Sciences, INDIA
| | - Shaik Mahammad Ghouse
- NIPER Hyderabad: National Institute of Pharmaceutical Education and Research Hyderabad, Chemical Sciences, INDIA
| | - Swayamsiddha Kar
- Sri Satya Sai Institute of Higher Learning: Sri Sathya Sai University, Department of chemistry, INDIA
| | - Sai Manohar Chelli
- Sri Satya Sai Institute of Higher Learning: Sri Sathya Sai University, Department of chemistry, INDIA
| | - Srinivas Reddy Dannarm
- NIPER Hyderabad: National Institute of Pharmaceutical Education and Research Hyderabad, Pharmaceutical analysis, INDIA
| | - Jitendra Gour
- NIPER Hyderabad: National Institute of Pharmaceutical Education and Research Hyderabad, Chemical Sciences, INDIA
| | - Rajesh Sonti
- NIPER Hyderabad: National Institute of Pharmaceutical Education and Research Hyderabad, Pharmaceutical analysis, INDIA
| | - Srinivas Nanduri
- National Institute of Pharmaceutical Education & Research, Process Chemistry, Balanagar, 500037, Hyderabad, INDIA
| |
Collapse
|
11
|
Su F, Lai M, Zhao M, Song M, Hu X, Zhang J. t
‐BuOK‐Mediated Transition‐Metal‐Free Direct Olefination and Alkylation of Methyl
N
‐Heteroarenes with Primary Alcohols under Control of Temperature. ChemistrySelect 2022. [DOI: 10.1002/slct.202104454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Fangyao Su
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| | - Miao Lai
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| | - Mingqin Zhao
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| | - Mingzhou Song
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| | - Xin Hu
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| | - Junqin Zhang
- Flavors and Fragrance Engineering & Technology Research Center of Henan Province, College of Tobacco Science Henan Agricultural University 95 Wenhua Road Zhengzhou 450002 P. R. China
| |
Collapse
|
12
|
Bera A, Kabadwal LM, Bera S, Banerjee D. Recent advances on non-precious metal-catalyzed C-H functionalization of N-heteroarenes. Chem Commun (Camb) 2021; 58:10-28. [PMID: 34874036 DOI: 10.1039/d1cc05899a] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
N-Heteroarenes are widely used for numerous medicinal applications, lifesaving drugs and show utmost importance as intermediates in chemical synthesis. This feature article highlights the recent advances, from 2015 to August 2021, on sp2 and sp3 C-H bond functionalization reactions of various N-heteroarenes catalyzed by non-precious transition metals (Mn, Co, Fe, Ni, etc.). The salient features of the report are: (i) the development of newer catalysis for Csp2-H activation of N-heteroarenes and categorized into alkylation, alkenylation, borylation, cyanation, and annulation reactions, (ii) recent advances on Csp3-H bond functionalization of N-heteroarenes considering newer approaches for alkylation as well as alkenylation processes, and (iii) synthetic applications and practical utility of the catalytic protocols utilized for late-stage drug development; (iv) scope for the development of newer catalytic protocols along with mechanistic studies and detail mechanistic findings of various important processes.
Collapse
Affiliation(s)
- Atanu Bera
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand, India.
| | - Lalit Mohan Kabadwal
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand, India.
| | - Sourajit Bera
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand, India.
| | - Debasis Banerjee
- Department of Chemistry, Laboratory of Catalysis and Organic Synthesis, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand, India.
| |
Collapse
|
13
|
Balamurugan G, Ramesh R. Nickel(II)‐Catalyzed Selective
(E)
‐Olefination of Methyl Heteroarenes Using Benzyl Alcohols via Acceptorless Dehydrogenative Coupling Reaction. ChemCatChem 2021. [DOI: 10.1002/cctc.202101455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gunasekaran Balamurugan
- Centre for Organometallic Chemistry School of Chemistry Bharathidasan University Tiruchirappalli 620 024 Tamilnadu India
| | - Rengan Ramesh
- Centre for Organometallic Chemistry School of Chemistry Bharathidasan University Tiruchirappalli 620 024 Tamilnadu India
| |
Collapse
|
14
|
Rai P, Waiba S, Maji K, Sahoo D, Maji B. Cooperative Lewis Acid Catalysis for the Enantioselective C(sp 3)-H Bond Functionalizations of 2-Alkyl Azaarenes. Org Lett 2021; 23:8888-8893. [PMID: 34752705 DOI: 10.1021/acs.orglett.1c03387] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein, we describe the enantioselective C(sp3)-H bond functionalizations of 2-alkyl azaarenes using a cooperative dual Lewis acid catalysis. An achiral Lewis acid activates the unactivated azaarene partner without the need for a strong base. Orthogonally, a chiral-at-metal Lewis acid catalyst enables LUMO lowering and induces chirality. This method tolerates a range of complex molecular scaffolds and exhibits good to excellent yields and selectivity while accepting a wide variety of functional groups.
Collapse
Affiliation(s)
- Pramod Rai
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Satyadeep Waiba
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Kakoli Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Dibyaranjan Sahoo
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Biplab Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| |
Collapse
|
15
|
Mondal A, Sharma R, Pal D, Srimani D. Manganese catalyzed switchable C-alkylation/alkenylation of fluorenes and indene with alcohols. Chem Commun (Camb) 2021; 57:10363-10366. [PMID: 34541595 DOI: 10.1039/d1cc03529k] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The usage of earth-abundant, nontoxic transition metals in place of rare noble metals is a central goal in catalysis. This would be especially interesting when the reactivity and selectivity patterns can be tuned. Herein, we introduced the first Mn-catalyzed selective C-alkylation and olefination of fluorene, and indene with alcohols. Various substrates including benzylic, heteroaromatic, and aliphatic primary and secondary alcohols are employed as alkylating agents. Mechanistic investigations and a kinetic study underpin the involvement of the olefinated intermediate to furnish the alkylated product.
Collapse
Affiliation(s)
- Avijit Mondal
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Rahul Sharma
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Debjyoti Pal
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Dipankar Srimani
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| |
Collapse
|
16
|
Das K, Barman MK, Maji B. Advancements in multifunctional manganese complexes for catalytic hydrogen transfer reactions. Chem Commun (Camb) 2021; 57:8534-8549. [PMID: 34369488 DOI: 10.1039/d1cc02512k] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Catalytic hydrogen transfer reactions have enormous academic and industrial applications for the production of diverse molecular scaffolds. Over the past few decades, precious late transition-metal catalysts were employed for these reactions. The early transition metals have recently gained much attention due to their lower cost, less toxicity, and overall sustainability. In this regard, manganese, which is the third most abundant transition metal in the Earth's crust, has emerged as a viable alternative. However, the key to the success of such manganese-based complexes lies in the multifunctional ligand design and choice of appropriate ancillary ligands, which helps them mimic and, even in some cases, supersede noble metals' activities. The metal-ligand bifunctionality, achieved via deprotonation of the acidic C-H or N-H bonds, is one of the powerful strategies employed for this purpose. Alongside, the ligand hemilability in which a weakly chelating group tunes in between the coordinated and uncoordinated stages could effectively stabilize the reactive intermediates, thereby facilitating substrate activation and catalysis. Redox non-innocent ligands acting as an electron sink, thereby helping the metal center in steps gaining or losing electrons, and non-classical metal-ligand cooperativity has also played a significant role in the ligand design for manganese catalysis. The strategies were not only employed for the chemoselective hydrogenation of different reducible functionalities but also for the C-X (X = C/N) coupling reactions via HT and downstream cascade processes. This article features multifunctional ligand-based manganese complexes, highlighting the importance of ligand design and choice of ancillary ligands for achieving the desired catalytic activity and selectivity for HT reactions. We have also discussed the detailed reaction pathways for metal complexes involving bifunctionality, hemilability, redox activity, and indirect metal-ligand cooperativity. The synthetic utilization of those complexes in different organic transformations has also been detailed.
Collapse
Affiliation(s)
- Kuhali Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India.
| | | | | |
Collapse
|
17
|
Abstract
Quinoxalines are observed in several bioactive molecules and have been widely employed in designing molecules for DSSC's, optoelectronics, and sensing applications. Therefore, developing newer synthetic routes as well as novel ways for their functionalization is apparent.
Collapse
Affiliation(s)
- Gauravi Yashwantrao
- Department of Speciality Chemicals Technology
- Institute of Chemical Technology
- Mumbai-400019
- India
| | - Satyajit Saha
- Department of Speciality Chemicals Technology
- Institute of Chemical Technology
- Mumbai-400019
- India
| |
Collapse
|