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Shekhawat B, Gahlaut PS, Gautam D, Jana B. N-Alkylation of amines with primary/secondary alcohols using a novel cobalt(II) inverse triazolyl-pyridine complex. Chem Commun (Camb) 2024; 60:8581-8584. [PMID: 39045651 DOI: 10.1039/d4cc01996b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Herein, we report a highly effective homogeneous methodology for the N-alkylation of amines with primary and secondary alcohols using a Co(II)-complex of an inverse triazolyl-pyridine ligand. The developed methodology tolerates various functional groups to produce the desired N-alkylated products in up to 98% yield. A number of control experiments establish that the developed methodology follows a hydrogen auto-transfer (HAT) pathway.
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Affiliation(s)
- Bhawana Shekhawat
- Organometallic and Supramolecular Chemistry Laboratory, Department of Chemistry, Malaviya National Institute of Technology Jaipur, JLN Marg, Jhalana Gram, Malviya Nagar, Jaipur, Rajasthan, 302017, India.
| | - Puneet Singh Gahlaut
- Organometallic and Supramolecular Chemistry Laboratory, Department of Chemistry, Malaviya National Institute of Technology Jaipur, JLN Marg, Jhalana Gram, Malviya Nagar, Jaipur, Rajasthan, 302017, India.
| | - Deepak Gautam
- Organometallic and Supramolecular Chemistry Laboratory, Department of Chemistry, Malaviya National Institute of Technology Jaipur, JLN Marg, Jhalana Gram, Malviya Nagar, Jaipur, Rajasthan, 302017, India.
| | - Barun Jana
- Organometallic and Supramolecular Chemistry Laboratory, Department of Chemistry, Malaviya National Institute of Technology Jaipur, JLN Marg, Jhalana Gram, Malviya Nagar, Jaipur, Rajasthan, 302017, India.
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2
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Jana D, Roy S, Naskar S, Halder S, Kanrar G, Pramanik K. Potent pincer-zinc catalyzed homogeneous α-alkylation and Friedländer quinoline synthesis reaction of secondary alcohols/ketones with primary alcohols. Org Biomol Chem 2024; 22:6393-6408. [PMID: 39056136 DOI: 10.1039/d4ob00988f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Herein, we describe an air- and moisture-stable, homogeneous zinc catalyst stabilised using an electron deficient N^N^N pincer-type ligand. This ternary, penta-coordinated neutral molecular catalyst [Zn(N^N^N)Cl2] selectively produces α-alkylated ketone derivatives (14 examples) through a one-pot acceptorless dehydrogenative coupling (ADC) reaction between secondary and primary alcohols using the borrowing hydrogen (BH) approach in good to excellent isolated yields (up to 93%). It is worth noting that this catalyst also provides an eco-friendly route for the synthesis of quinoline derivatives (30 examples) using 2-aminobenzyl alcohols as alkylating agents via successive dehydrogenative coupling and N-annulation reactions. This cost effective, easy to synthesize and environmentally benign catalyst shows excellent stability in catalytic cycles under open-air conditions, as evident from its high turnover number (∼104), and is activated by using a catalytic amount of base under milder conditions.
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Affiliation(s)
- Debashis Jana
- Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sima Roy
- Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Srijita Naskar
- Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Supriyo Halder
- Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Gopal Kanrar
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata-700016, India
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3
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Kumar Chaudhary V, Kukreti P, Sharma K, Kumar K, Singh S, Kumari S, Ghosh K. A sustainable strategic approach for N-alkylation of amines with activation of alcohols triggered via a hydrogen auto-transfer reaction using a Pd(II) complex: evidence for metal-ligand cooperativity. Dalton Trans 2024; 53:8740-8749. [PMID: 38712566 DOI: 10.1039/d4dt00864b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N-alkylation of amines and indole synthesis where H2O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal-ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle.
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Affiliation(s)
- Virendra Kumar Chaudhary
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Prashant Kukreti
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Keshav Sharma
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Kapil Kumar
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Sain Singh
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Sheela Kumari
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
| | - Kaushik Ghosh
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
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4
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Samanta A, Behera P, Chaubey A, Mondal A, Pal D, Mohar K, Roy L, Srimani D. Experimental and theoretical insights for designing Zn 2+ complexes to trigger chemo-selective hetero-coupling of alcohols. Chem Commun (Camb) 2024; 60:4056-4059. [PMID: 38505958 DOI: 10.1039/d4cc00864b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Designing well-defined Zn-complexes for sustainable dehydrogenative catalysis overcoming the difficulties associated with activating Zn2+(d10)-metal species is considered paramount goal in catalysis. Herein, we explore the plausibility of β-alkylation of secondary alcohols with primary alcohols by well-defined 3d10 Zn-complexes. Detailed organometallic and catalytic investigations, in conjunction with computational analyses, were conducted to ascertain the potential involvement of the catalyst at various stages of the catalytic process.
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Affiliation(s)
- Arup Samanta
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Prativa Behera
- Institute of Chemical Technology Mumbai, IOC Odisha Campus Bhubaneswar, Bhubaneswar, Odisha 751013, India.
| | - Amit Chaubey
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Avijit Mondal
- 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.
| | - Kailash Mohar
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
| | - Lisa Roy
- Institute of Chemical Technology Mumbai, IOC Odisha Campus Bhubaneswar, Bhubaneswar, Odisha 751013, India.
| | - Dipankar Srimani
- Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
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5
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Li J, Mao A, Hu X, Wang L, Wang D, Duan ZC. Preparation of a novel cadmium-containing coordination polymer and catalytic application in the synthesis of N-alkylated aminoquinoline derivatives via the borrowing hydrogen approach. Dalton Trans 2024; 53:5064-5072. [PMID: 38375833 DOI: 10.1039/d3dt04221a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Herein, we report an efficient and straightforward approach for the synthesis of N-alkylated aminoquinoline derivatives by recyclable Cd-containing coordination polymer-catalyzed reactions of aminoquinolines with primary alcohols via the borrowing hydrogen strategy. In this work, a new type of coordination polymer [Cd(CIA)(phen)2(H2O)]n was successfully designed and fabricated. The molecular structure was corroborated by single-crystal X-ray diffraction and fully characterized by PXRD, FT-IR, TGA, and XPS. Importantly, this polymer revealed high catalytic activity for the N-alkylation reaction of 2-aminoquinoline and 8-aminoquinoline with inexpensive and low-toxicity alcohols as alkylating agents in excellent yields up to 95%. Interestingly, the present synthetic protocol was successfully applied for the gram-level synthesis of several biologically active compounds. In addition, several control reactions were carried out to investigate the possible mechanisms of this transformation. Finally, recycling experiments indicated that the cadmium coordination polymer showed good recovery performance for borrowing hydrogen reactions.
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Affiliation(s)
- Jiahao Li
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
| | - Anruo Mao
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Xinyu Hu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
| | - Likui Wang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
| | - Dawei Wang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
| | - Zheng-Chao Duan
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, PR China.
- School of Chemical and Environmental Engineering, Hubei Minzu University, Enshi 445000, PR China
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Guin AK, Pal S, Chakraborty S, Chakraborty S, Paul ND. Oxygen Dependent Switchable Selectivity during Ruthenium Catalyzed Selective Synthesis of C3-Alkylated Indoles and Bis(indolyl)methanes. J Org Chem 2023. [PMID: 38015094 DOI: 10.1021/acs.joc.3c01191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Herein, we report a ligand-centered redox-controlled oxygen-dependent switchable selectivity during ruthenium-catalyzed selective synthesis of C3-alkylated indoles and bis(indolyl)methanes (BIMs). A wide variety of C3-alkylated indoles and BIMs were prepared selectively in moderate to good isolated yields by coupling a wide variety of indoles and alcohols, catalyzed by a well-defined, air-stable, and easy-to-prepare Ru(II)-catalyst (1a) bearing a redox-active tridentate pincer (L1a). Catalyst 1a efficiently catalyzed the C3-alkylation of indoles under an argon atmosphere while, under an oxygen environment, exclusively producing the BIMs. A few drug molecules containing BIMs were also synthesized efficiently. 1a exhibited excellent chemoselectivity with alcohols containing internal carbon-carbon double bonds. Mechanistic investigation revealed that the coordinated azo-aromatic ligand actively participates during the catalysis. During the dehydrogenation of alcohols, the azo-moiety of the ligand stores the hydrogen removed from the alcohols and subsequently transfers the hydrogen to the alkylideneindolenine intermediate, forming the C3-alkylated indoles. While under an oxygen environment, the transfer of hydrogen from the ligand scaffold to the molecular oxygen generates H2O2, leaving no scope for hydrogenation of the alkylideneindolenine intermediate, rather than it undergoing 1,4-Michael-type addition forming the BIMs.
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Affiliation(s)
- Amit Kumar Guin
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhasree Pal
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhajit Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Santana Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Nanda D Paul
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
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7
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Pazur EJ, Tasker NR, Wipf P. C3-Functionalization of indoles with α-heteroaryl-substituted methyl alcohols. Org Biomol Chem 2023; 21:8651-8657. [PMID: 37873703 DOI: 10.1039/d3ob01432k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The transition metal-free Cs2CO3/Oxone®-mediated C3-alkylation of indoles proceeds in moderate to high yields with a variety of C4-C7 functionalized indoles and is applicable to 2-, 3- and 4-hydroxymethyl pyridines and related electron-deficient heterocycles, permitting novel late-stage drug functionalizations. Preliminary mechanistic studies support a hydrogen autotransfer-type chain process starting with an initial oxidation of the alcohol to the corresponding aldehyde, followed by a subsequent condensation onto indole and reduction/hydride delivery from another equivalent of the primary alcohol.
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Affiliation(s)
- Ethan J Pazur
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| | - Nikhil R Tasker
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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Vyas V, Maurya P, Indra A. Metal-organic framework-derived CoN x nanoparticles on N-doped carbon for selective N-alkylation of aniline. Chem Sci 2023; 14:12339-12344. [PMID: 37969583 PMCID: PMC10631233 DOI: 10.1039/d3sc02515b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/09/2023] [Indexed: 11/17/2023] Open
Abstract
N-alkylation of anilines by alcohols can be used as an efficient strategy to synthesise a wide range of secondary amines. In this respect, a hydrogen borrowing methodology has been explored using precious metal-based catalysts. However, the utilisation of cheap and readily available transition metal based catalysts is required for large-scale applications. In this work, we have reported metal-organic framework-derived CoNx@NC catalysts for the selective N-alkylation of anilines with different types of alcohols. The Co-N coordination in CoNx@NC was found to be extremely important to improve the conversion efficiency and yield of the product. As a result, CoNx@NC produced 99% yield of the desired amines, which is far better than that of Co@C (yield = 65%). In addition, CoNx@NC showed remarkable recyclability for six cycles with a minimum drop in the yield of the desired product.
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Affiliation(s)
- Ved Vyas
- Department of Chemistry, Indian Institute of Technology (BHU) Varanasi UP-221005 India
| | - Priyanka Maurya
- Department of Chemistry, Indian Institute of Technology (BHU) Varanasi UP-221005 India
| | - Arindam Indra
- Department of Chemistry, Indian Institute of Technology (BHU) Varanasi UP-221005 India
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9
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Swatiputra AA, Mukherjee D, Dinda S, Roy S, Pramanik K, Ganguly S. Electron transfer catalysis mediated by 3d complexes of redox non-innocent ligands possessing an azo function: a perspective. Dalton Trans 2023; 52:15627-15646. [PMID: 37792473 DOI: 10.1039/d3dt02567e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
It was first reported almost two decades ago that ligands with azo functions are capable of accepting electron(s) upon coordination to produce azo-anion radical complexes, thereby exhibiting redox non-innocence. Over the past two decades, there have been numerous reports of such complexes along with their structures and diverse characteristics. The ability of a coordinated azo function to accept one or more electron(s), thereby acting as an electron reservoir, is currently employed to carry out electron transfer catalysis since they can undergo redox transformation at mild potentials due to the presence of energetically accessible energy levels. The cooperative involvement of redox non-innocent ligand(s) containing an azo group and the coordinated metal centre can adjust and modulate the Lewis acidity of the latter through selective ligand-centred redox events, thereby manipulating the capacity of the metal centre to bind to the substrate. We have summarized the list of first row transition metal complexes of iron, cobalt, nickel, copper and zinc with redox non-innocent ligands incorporating an azo function that have been exploited as electron transfer catalysts to effectuate sustainable synthesis of a wide variety of useful chemicals. These include ketazines, pyrimidines, benzothiazole, benzoxazoles, N-acyl hydrazones, quinazoline-4(3)H-ones, C-3 alkylated indoles, N-alkylated anilines and N-alkylated heteroamines. The reaction pathways, as demonstrated by catalytic loops, reveal that the azo function of a coordinated ligand can act as an electron sink in the initial steps to bring about alcohol oxidation and thereafter, they serve as an electron pool to produce the final products either via HAT or PCET processes.
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Affiliation(s)
- Alok Apan Swatiputra
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
| | - Debaarjun Mukherjee
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
| | - Soumitra Dinda
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
| | - Subhadip Roy
- Department of Chemistry, The ICFAI University Tripura, Tripura 799210, India
| | - Kausikisankar Pramanik
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India
| | - Sanjib Ganguly
- Department of Chemistry, St. Xavier's College (Autonomous), Kolkata - 700016, India.
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Guin AK, Pal S, Chakraborty S, Chakraborty S, Paul ND. N-Alkylation of Amines by C1-C10 Aliphatic Alcohols Using A Well-Defined Ru(II)-Catalyst. A Metal-Ligand Cooperative Approach. J Org Chem 2023; 88:5944-5961. [PMID: 37052217 DOI: 10.1021/acs.joc.3c00313] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
A Ru(II)-catalyzed efficient and selective N-alkylation of amines by C1-C10 aliphatic alcohols is reported. The catalyst [Ru(L1a)(PPh3)Cl2] (1a) bearing a tridentate redox-active azo-aromatic pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (L1a) is air-stable, easy to prepare, and showed wide functional group tolerance requiring only 1.0 mol % (for N-methylation and N-ethylation) and 0.1 mol % of catalyst loading for N-alkylation with C3-C10 alcohols. A wide array of N-methylated, N-ethylated, and N-alkylated amines were prepared in moderate to good yields via direct coupling of amines and alcohols. 1a efficiently catalyzes the N-alkylation of diamines selectively. It is even suitable for synthesizing N-alkylated diamines using (aliphatic) diols producing the tumor-active drug molecule MSX-122 in moderate yield. 1a showed excellent chemo-selectivity during the N-alkylation using oleyl alcohol and monoterpenoid β-citronellol. Control experiments and mechanistic investigations revealed that the 1a-catalyzed N-alkylation reactions proceed via a borrowing hydrogen transfer pathway where the hydrogen removed from the alcohol during the dehydrogenation step is stored in the ligand backbone of 1a, which in the subsequent steps transferred to the in situ formed imine intermediate to produce the N-alkylated amines.
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Affiliation(s)
- Amit Kumar Guin
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhasree Pal
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhajit Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Santana Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Nanda D Paul
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
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Pal S, Das S, Chakraborty S, Khanra S, Paul ND. Zn(II)-Catalyzed Multicomponent Sustainable Synthesis of Pyridines in Air. J Org Chem 2023; 88:3650-3665. [PMID: 36854027 DOI: 10.1021/acs.joc.2c02867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Herein, we report a Zn(II)-catalyzed solvent-free sustainable synthesis of tri- and tetra-substituted pyridines using alcohols as the primary feedstock and NH4OAc as the nitrogen source. Using a well-defined air-stable Zn(II)-catalyst, 1a, featuring a redox-active tridentate azo-aromatic pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (La), a wide variety of unsymmetrical 2,4,6-substituted pyridines were prepared by three-component coupling of primary and secondary alcohols with NH4OAc. Catalyst 1a is equally compatible with the four-component coupling. Unsymmetrical 2,4,6-substituted pyridines were also prepared via a four-component coupling of a primary alcohol with two different secondary alcohols and NH4OAc. A series of tetra-substituted pyridines were prepared up to 67% yield by coupling primary and secondary alcohols with 1-phenylpropan-1-one or 1,2-diphenylethan-1-one and NH4OAc. The 1a-catalyzed reactions also proceeded efficiently upon replacing the secondary alcohols with the corresponding ketones, producing the desired tri- and tetra-substituted pyridines in higher yields in a shorter reaction time. A few control experiments were performed to unveil the mechanistic aspects, which indicates that the active participation of the aryl-azo ligand during catalysis enables the Zn(II)-complex to act as an efficient catalyst for the present multicomponent reactions. Aerial oxygen acts as an oxidant during the Zn(II)-catalyzed dehydrogenation of alcohols, producing H2O and H2O2 as byproducts.
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Affiliation(s)
- Subhasree Pal
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Siuli Das
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhajit Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhankar Khanra
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Nanda D Paul
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
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