1
|
Rani P, Prakash M, Samanta S. Organobase-catalyzed Mannich reaction of cyclic N-sulfonyl imines and 1,2-diketones: a sustainable approach to 4-(3-arylquinoxalin-2-ylmethyl)sufamidates. Tetrahedron Lett 2023. [DOI: 10.1016/j.tetlet.2023.154490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
|
2
|
Prakash M, Halder S, Guin S, Samanta S. Swapping Copper-Catalytic Process: Selective Access to Pyrazoles and Conjugated Ketimines from Oxime Acetates and Cyclic Sulfamidate Imines. Chem Asian J 2023; 18:e202201114. [PMID: 36583485 DOI: 10.1002/asia.202201114] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/16/2022] [Accepted: 12/29/2022] [Indexed: 12/31/2022]
Abstract
A powerful CuCl-catalyzed sequential one-pot reaction of aryl methyl ketoxime acetates with cyclic N-sulfonyl imines followed by elimination in the presence of base is reported. This hydrazine-free method conveniently makes C-C and N-N bonds via a radical cleavage of the N-O bond, delivering a special class of C3-hydroxyarylated pyrazoles in good yields. Surprisingly, while employing CuI as a catalyst instead of CuCl, the reaction proceeds through a non-radical pathway which embodies a new tactic for the high-yielding access to value-added conjugated N-unsubstituted ketimines. Moreover, additive-free approach to sulfamidate-fused-pyrazoles was achieved by successfully catalyzing addition and oxidative N-N bond-making reactions by CuI and CuCl, respectively. Significantly, our novel technique could convert the prepared ketimines into the pharmacologically recognized 6H-benzo[c]chromene frameworks.
Collapse
Affiliation(s)
- Meher Prakash
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Sajal Halder
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Soumitra Guin
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Sampak Samanta
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| |
Collapse
|
3
|
Cheng D, Meng XZ, Tian F, Yan D, Wang X, Qian X, Wang J. Crystal structure and Hirshfeld surface analysis of 4-(3-methoxyphenyl)-2,6-diphenylpyridine. Acta Crystallogr E Crystallogr Commun 2022; 78:932-935. [PMID: 36072513 PMCID: PMC9443808 DOI: 10.1107/s2056989022007812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 08/03/2022] [Indexed: 11/17/2022]
Abstract
The title compound was obtained via the reaction of (1E,2E)-3-(3-methoxyphenyl)-1-phenylprop-2-en-1-one with ethyl 2-oxopropanoate, using NH4I as a catalyst. In the molecule, the four rings are not in the same plane, the pyridine ring being inclined to the benzene rings by 17.26 (6), 56.16 (3) and 24.50 (6)°. In the crystal, molecules are linked by C—H⋯π interactions into a three-dimensional network. The title compound, C24H19NO, was obtained via the reaction of (1E,2E)-3-(3-methoxyphenyl)-1-phenylprop-2-en-1-one with ethyl 2-oxopropanoate, using NH4I as a catalyst. The compound crystallizes in the monoclinic space group I2/a. In the molecule, the four rings are not in the same plane, the pyridine ring being inclined to the benzene rings by 17.26 (6), 56.16 (3) and 24.50 (6)°. In the crystal, molecules are linked by C—H⋯π interactions into a three-dimensional network. To further analyse the intermolecular interactions, a Hirshfeld surface analysis was performed. Hirshfeld surface analysis indicates that the most abundant contributions to the crystal packing are from H⋯H (50.4%), C⋯H/H⋯C (37.9%) and O⋯H/H⋯O (5.1%) interactions.
Collapse
|
4
|
Patel AK, Rathor SS, Samanta S. Regioselective access to di- and trisubstituted pyridines via a metal-oxidant-solvent-free domino reaction involving 3-chloropropiophenones. Org Biomol Chem 2022; 20:6759-6765. [PMID: 35972042 DOI: 10.1039/d2ob01193j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A remarkable metal-oxidant-solvent- and base-free domino route for regioselective access to a wide range of 2,4-di- and 2,3,4/6-trisubstituted pyridines including carbo- and heterocyclic fused pyridines is reported. This [3C + 2C + 1N] cyclization reaction occurs between 3-chloropropiophenones (3C units), enolizable acyclic/cyclic ketones (2C sources) and NH4OAc as a robust N source under neat conditions under an open atmosphere, producing new C=C and C=N-C bonds in highly chemo- and regioselective manners. Interestingly, this eco-friendly method has many positive features: excellent functional group tolerance, broad substrate scope, good to excellent regioselectivities, promising yields, no-unwanted products, neutral reaction conditions and appropriateness for large-scale synthesis. Mechanism studies reveal that the in situ generated β-amino ketone from 3-chloropropiophenone and an ammonium salt undergoes C=N bond formation with a ketone followed by an intramolecular cyclization process (C=C bond), which are the decisive steps for pyridine synthesis.
Collapse
Affiliation(s)
- Ashvani Kumar Patel
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552, India.
| | - Shikha Singh Rathor
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552, India.
| | - Sampak Samanta
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552, India.
| |
Collapse
|
5
|
Goud SB, Guin S, Prakash M, Samanta S. Cu(OAc) 2/DABCO-mediated domino reaction of vinyl malononitriles with cyclic sulfamidate imines: access to 6-hydroxyaryl-2-aminonicotinonitriles. Org Biomol Chem 2022; 20:352-357. [PMID: 34931209 DOI: 10.1039/d1ob02095a] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A novel Cu(II)-salt/DABCO-mediated one-pot access to a myriad of highly substituted biologically relevant 2-aminonicotinonitriles possessing a resourceful phenolic moiety with satisfactory yields is reported. This method involves cyclic sulfamidate imines as 1C1N sources and different kinds of acyclic/cyclic vinyl malononitriles as 4C sources for pyridine synthesis via a vinylogous Mannich-cycloaromatization sequence process, creating two new C-N bonds under mild conditions. Importantly, this de novo strategy is applicable to gram-scale syntheses, underlining the method's practicability and allowing for a wide range of substrates with excellent functional group tolerance.
Collapse
Affiliation(s)
- S Banuprakash Goud
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552 India.
| | - Soumitra Guin
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552 India.
| | - Meher Prakash
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552 India.
| | - Sampak Samanta
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, 453552 India.
| |
Collapse
|
6
|
Pan Y, Ren W, Zhang Z, Luo F, Hou X, Li X, Yang YF, Wang Y. Tandem 1,6-addition/cyclopropanation/rearrangement reaction of vinylogous para-quinone methides with 3-chlorooxindoles: construction of vicinal quaternary carbon centers. Org Chem Front 2022. [DOI: 10.1039/d2qo00471b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel tandem 1,6-addition/cyclopropanation/rearrangement reaction of vinylogous para-quinone methides with 3-chlorooxindoles has been developed, providing dispirooxindole–cyclopentane–cyclohexadienones with vicinal quaternary carbon centers.
Collapse
Affiliation(s)
- Yuan Pan
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Weiwu Ren
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology (QNLM), Qingdao 266237, China
| | - Zhanhao Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Fengbiao Luo
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Xiaohan Hou
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Xiaoyang Li
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Yun-Fang Yang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Yang Wang
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology (QNLM), Qingdao 266237, China
| |
Collapse
|
7
|
Meng X, Cheng D, Wang S, Zhao X, Chen J. NH4I-Catalyzed Formal [4+2] Cycloaddition of α,β-Unsaturated O-Acetyl Oxime with Alkyl Pyruvate for Rapid Substituted Pyridine Formation. HETEROCYCLES 2022. [DOI: 10.3987/com-22-14688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
8
|
Shabalin DA. Recent advances and future challenges in the synthesis of 2,4,6-triarylpyridines. Org Biomol Chem 2021; 19:8184-8204. [PMID: 34499071 DOI: 10.1039/d1ob01310f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
2,4,6-Triarylpyridines are key building blocks to access functional molecules that are used in the design of advanced materials, metal-organic frameworks, supramolecules, reactive chemical intermediates and drugs. A number of synthetic protocols to construct this heterocyclic scaffold have been developed to date, the most recent of which (2015-present) are included and discussed in the present review. An emphasis has been placed on the utility of each synthetic approach in view of the scope of aryl/hetaryl substituents, limitations and an outlook of each method to be used in applied sciences.
Collapse
Affiliation(s)
- Dmitrii A Shabalin
- A.E. Favorsky Irkutsk Institute of Chemistry SB RAS, 1 Favorsky St, Irkutsk, 664033, Russian Federation.
| |
Collapse
|
9
|
Guin S, Majee D, Samanta S. Unmasking the reverse reactivity of cyclic N-sulfonyl ketimines: multifaceted applications in organic synthesis. Chem Commun (Camb) 2021; 57:9010-9028. [PMID: 34498642 DOI: 10.1039/d1cc03439a] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The chemistry related to the exploration of cyclic N-sulfonyl ketimines and their derivatives has attracted significant attention in the last few decades because of their intriguing structures and properties. They serve broadly as reactive synthons in various reactions to create a diverse set of synthetically and biologically attractive molecules. Furthermore, these moieties, which possess multiple heteroatoms (N, O and S), display or can enhance many biological activities. In the case of synthetic reactions, chemists mainly focus on the chemical manipulation of the highly reactive prochiral CN bond of N-sulfonyl ketimines. Besides their traditional role as electrophiles, N-sulfonyl ketimines possess α-Csp3-H protons, and thus behave as potential carbonucleophiles, where they can undergo several C-X (X = C, N and O) bond-forming reactions with different types of electrophiles under various conditions to form a wide range of fascinating asymmetric and non-asymmetric versions of fused heterocycles, carbocycles, spiro-fused skeletons, pyridines, pyrroles, etc. Herein, we highlight the recent examples from our research work and others covering the scope of cyclic N-sulfonyl ketimines as useful carbonucleophiles. In addition, the detailed mechanistic studies of the above-mentioned reactions are also presented.
Collapse
Affiliation(s)
- Soumitra Guin
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India.
| | - Debashis Majee
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India.
| | - Sampak Samanta
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India.
| |
Collapse
|
10
|
Singh G, Pandey R, Pankhade YA, Fatma S, Anand RV. Construction of Oxygen- and Nitrogen-based Heterocycles from p-Quinone Methides. CHEM REC 2021; 21:4150-4173. [PMID: 34369640 DOI: 10.1002/tcr.202100137] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/25/2021] [Accepted: 06/28/2021] [Indexed: 01/08/2023]
Abstract
In the last few years, there has been an explosive growth in the area of para-quinone methide (p-QM) chemistry. This boom is actually due to the unique reactivity pattern of p-QMs, and also their remarkable synthetic applications. In fact, p-QMs serve as synthons for unsymmetrical diaryl- and triarylmethanes, and also for the construction of diverse range of carbocycles and heterocycles. In the last few years, a wide range of structurally complex heterocyclic frameworks could be accessed through the synthetic transformations of structurally modified stable p-QMs. Therefore, the main focus of this review article is to cover the recent advancements in the transition-metal, Lewis acid and base-catalyzed/mediated synthetic transformations of the stable p-quinone methides (p-QMs) to oxygen- and nitrogen-containing heterocycles.
Collapse
Affiliation(s)
- Gurdeep Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, SAS Nagar, Manauli (PO), Punjab, 140306
| | - Rajat Pandey
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, SAS Nagar, Manauli (PO), Punjab, 140306
| | - Yogesh A Pankhade
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, SAS Nagar, Manauli (PO), Punjab, 140306
| | - Shaheen Fatma
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, SAS Nagar, Manauli (PO), Punjab, 140306
| | - Ramasamy Vijaya Anand
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, Knowledge City, SAS Nagar, Manauli (PO), Punjab, 140306
| |
Collapse
|
11
|
Yu KY, Deng YH, Ge XM, An XT, Shu PF, Cao YX, Zhao XH, Fan CA. Tandem (2 + 2) Annulation/Retro-4π Electrocyclization/Imino-Nazarov Cyclization Reaction of p-Quinone Methides with Ynamides: Expeditious Construction of Functionalized Aminoindenes. Org Lett 2021; 23:5885-5890. [PMID: 34279973 DOI: 10.1021/acs.orglett.1c02003] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A new tandem annulation of p-quinone methides (p-QMs) with ynamides is described. This cascade reaction features a unique combination of (2 + 2) annulation, retro-4π electrocyclization, and imino-Nazarov cyclization, wherein vinyl p-quinone methides (p-VQMs) as one of the key intermediates have been identified chemically. Significantly, an unusual structural reconstruction of p-QMs involving the cleavage of the C5-C6 bond and the late-stage formation of the C4-C6 bond is involved, leading to a methodology development for the construction of functionalized aminoindenes.
Collapse
Affiliation(s)
- Ke-Yin Yu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Yu-Hua Deng
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Xiao-Min Ge
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Xian-Tao An
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Peng-Fei Shu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Ye-Xing Cao
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Xian-He Zhao
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| | - Chun-An Fan
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Nanlu, Lanzhou 730000, China
| |
Collapse
|
12
|
Guin S, Majee D, Samanta S. Recent Advances in Visible‐Light‐Driven Photocatalyzed γ‐Cyanoalkylation Reactions. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Soumitra Guin
- Department of Chemistry Indian Institute of TechnologyIndore 453552 Indore India
| | - Debashis Majee
- Department of Chemistry Indian Institute of TechnologyIndore 453552 Indore India
| | - Sampak Samanta
- Department of Chemistry Indian Institute of TechnologyIndore 453552 Indore India
| |
Collapse
|
13
|
Prakash M, Lodhi R, Samanta S. Substrate-Controlled Domino Reaction of N-Sulfonyl Ketimines with 2-Aroyl-1-chlorocyclopropanecarboxylates: Access to Cyclopenta[c]chromenes and Benzo[f]cyclopenta[d][1,2]thiazepine Dioxides. J Org Chem 2021; 86:6721-6733. [DOI: 10.1021/acs.joc.1c00459] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Meher Prakash
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, Madhya Pradesh 453552, India
| | - Rajni Lodhi
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, Madhya Pradesh 453552, India
| | - Sampak Samanta
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, Madhya Pradesh 453552, India
| |
Collapse
|
14
|
Shabalin DA, Dvorko MY, Schmidt EY, Trofimov BA. Regiocontrolled synthesis of 2,4,6-triarylpyridines from methyl ketones, electron-deficient acetylenes and ammonium acetate. Org Biomol Chem 2021; 19:2703-2715. [PMID: 33667288 DOI: 10.1039/d1ob00193k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A novel one-pot two-step approach for the synthesis of 2,4,6-triarylpyridines via t-BuOK/DMSO-promoted C-vinylation of a variety of methyl ketones with electron-deficient acetylenes (alkynones) followed by a cyclization of the in situ generated unsaturated 1,5-dicarbonyl species with ammonium acetate has been developed. This approach possesses competitive advantages such as high regioselectivity, available starting materials and the absence of transition-metal catalysts, oxidants and undesirable byproducts. A wide synthetic utility of the developed approach was demonstrated by the synthesis of trisubstituted, tetrasubstituted and fused pyridines.
Collapse
Affiliation(s)
- Dmitrii A Shabalin
- A.E. Favorsky Irkutsk Institute of Chemistry SB RAS, 1 Favorsky St, Irkutsk, 664033, Russian Federation.
| | | | | | | |
Collapse
|
15
|
Pham QH, Hyland CJT, Pyne SG. Five-membered cyclic sulfamidate imines: versatile scaffolds for organic synthesis. Org Biomol Chem 2020; 18:7467-7484. [PMID: 32930695 DOI: 10.1039/d0ob01568g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In recent years, five-membered ring cyclic sulfamidate imines (5H-1,2,3-oxathiazole 2,2-dioxides) have received increasing attention as useful precursors for the stereoselective synthesis of many valuable heterocycles. Bearing a reactive N-sulfonyl imine moiety as part of the stereodefined skeleton, this sulfamidate imine platform has been utilised as a substrate in many reactions, including nucleophilic additions and reductions, to prepare highly functionalised cyclic sulfamidates. In addition, cyclic sulfamidate imines can also readily participate as nucleophiles in many chemical transformations, owing to the acidic proton(s) adjacent to the imine moiety. This short review highlights recent developments involving cyclic sulfamidate imines, including their synthesis and reactivity, with a focus on stereoselective processes.
Collapse
Affiliation(s)
- Quoc Hoang Pham
- School of Chemistry and Molecular Bioscience, Molecular Horizons Research Institute, University of Wollongong, Wollongong, New South Wales 2522, Australia.
| | | | | |
Collapse
|
16
|
Guin S, Saha HK, Patel AK, Gudimella SK, Biswas S, Samanta S. 1,6-Aza-Michael addition of para-quinone methides with N-heterocycles catalyzed by Zn(OTf)2: A regioselective approach to N-diarylmethyl-substituted heterocycles. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131338] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|