1
|
Horbaczewskyj CS, Fairlamb IJS. Pd-Catalyzed Cross-Couplings: On the Importance of the Catalyst Quantity Descriptors, mol % and ppm. Org Process Res Dev 2022; 26:2240-2269. [PMID: 36032362 PMCID: PMC9396667 DOI: 10.1021/acs.oprd.2c00051] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Indexed: 12/26/2022]
Abstract
![]()
This Review examines parts per million (ppm) palladium
concentrations
in catalytic cross-coupling reactions and their relationship with
mole percentage (mol %). Most studies in catalytic cross-coupling
chemistry have historically focused on the concentration ratio between
(pre)catalyst and the limiting reagent (substrate), expressed as mol
%. Several recent papers have outlined the use of “ppm level”
palladium as an alternative means of describing catalytic cross-coupling
reaction systems. This led us to delve deeper into the literature
to assess whether “ppm level” palladium is a practically
useful descriptor of catalyst quantities in palladium-catalyzed cross-coupling
reactions. Indeed, we conjectured that many reactions could, unknowingly,
have employed low “ppm levels” of palladium (pre)catalyst,
and generally, what would the spread of ppm palladium look like across
a selection of studies reported across the vast array of the cross-coupling
chemistry literature. In a few selected examples, we have examined
other metal catalyst systems for comparison with palladium.
Collapse
Affiliation(s)
| | - Ian J. S. Fairlamb
- University of York, Heslington, York, North Yorkshire, YO10 5DD, United Kingdom
| |
Collapse
|
2
|
Sharma NK, Jena CK. Novel Cinnamic Acid Analogues: Synthesis of Aminotroponyl Acrylates by Pd(II)-Catalysed C(sp2)-H Olefination. Chem Commun (Camb) 2022; 58:8077-8080. [DOI: 10.1039/d2cc02276a] [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
Cinnamic acid, benzenoid scaffold, is a building block of various natural products. This report describes the synthesis of new non-benzenoid cinnamate analogs 3-(6-amino-7-oxocyclohepta-1,3,5-trien-1-yl)acrylates, obtained through Pd(II)-catalyzed C7-H olefination of 2-aminotropones...
Collapse
|
3
|
Balkenhohl M, Jangra H, Makarov IS, Yang S, Zipse H, Knochel P. A Predictive Model Towards Site-Selective Metalations of Functionalized Heterocycles, Arenes, Olefins, and Alkanes using TMPZnCl⋅LiCl. Angew Chem Int Ed Engl 2020; 59:14992-14999. [PMID: 32400069 PMCID: PMC7497272 DOI: 10.1002/anie.202005372] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Indexed: 01/02/2023]
Abstract
The development of a predictive model towards site-selective deprotometalation reactions using TMPZnCl⋅LiCl is reported (TMP=2,2,6,6-tetramethylpiperidinyl). The pKa values of functionalized N-, S-, and O-heterocycles, arenes, alkenes, or alkanes were calculated and compared to the experimental deprotonation sites. Large overlap (>80 %) between the calculated and empirical deprotonation sites was observed, showing that thermodynamic factors strongly govern the metalation regioselectivity. In the case of olefins, calculated frozen state energies of the deprotonated substrates allowed a more accurate prediction. Additionally, various new N-heterocycles were analyzed and the metalation regioselectivities rationalized using the predictive model.
Collapse
Affiliation(s)
- Moritz Balkenhohl
- Department of ChemistryLudwig-Maximilians-Universität MünchenButenandtstr. 5–1381377MunichGermany
| | - Harish Jangra
- Department of ChemistryLudwig-Maximilians-Universität MünchenButenandtstr. 5–1381377MunichGermany
| | - Ilya S. Makarov
- Department of ChemistryLudwig-Maximilians-Universität MünchenButenandtstr. 5–1381377MunichGermany
| | - Shu‐Mei Yang
- Department of ChemistryNational (Taiwan) Normal University88, Sec. 4, Tingchow RoadTaipei11677Taiwan, Republic of China
| | - Hendrik Zipse
- Department of ChemistryLudwig-Maximilians-Universität MünchenButenandtstr. 5–1381377MunichGermany
| | - Paul Knochel
- Department of ChemistryLudwig-Maximilians-Universität MünchenButenandtstr. 5–1381377MunichGermany
| |
Collapse
|
4
|
Balkenhohl M, Jangra H, Makarov IS, Yang S, Zipse H, Knochel P. A Predictive Model Towards Site‐Selective Metalations of Functionalized Heterocycles, Arenes, Olefins, and Alkanes using TMPZnCl⋅LiCl. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202005372] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Moritz Balkenhohl
- Department of Chemistry Ludwig-Maximilians-Universität München Butenandtstr. 5–13 81377 Munich Germany
| | - Harish Jangra
- Department of Chemistry Ludwig-Maximilians-Universität München Butenandtstr. 5–13 81377 Munich Germany
| | - Ilya S. Makarov
- Department of Chemistry Ludwig-Maximilians-Universität München Butenandtstr. 5–13 81377 Munich Germany
| | - Shu‐Mei Yang
- Department of Chemistry National (Taiwan) Normal University 88, Sec. 4, Tingchow Road Taipei 11677 Taiwan, Republic of China
| | - Hendrik Zipse
- Department of Chemistry Ludwig-Maximilians-Universität München Butenandtstr. 5–13 81377 Munich Germany
| | - Paul Knochel
- Department of Chemistry Ludwig-Maximilians-Universität München Butenandtstr. 5–13 81377 Munich Germany
| |
Collapse
|
5
|
Kumar NR, Agrawal AR, Zade SS. Abnormal Nucleophilic Substitution on Methoxytropone Derivatives: Steric Strategy to Synthesize 5-Substituted Azulenes. Chemistry 2019; 25:14064-14071. [PMID: 31364221 DOI: 10.1002/chem.201902702] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Indexed: 11/08/2022]
Abstract
Azulene is a non-alternant non-benzenoid aromatic system, and in turn, it possesses unusual photophysical properties. Azulene-based conjugated systems have received increasing interest in recent years as optoelectronic materials. Despite the routes available for the preparation of substituted azulene derivatives, there remain few methods that allow regioselective substitution on the seven-membered ring of azulenes due to the subtle reactivity difference among the various positions. This report explores the reactivity of substituted tropolones as the azulene precursors and also provides a new method to create 5-substituted azulenes. The reaction of cyanoacetate enolate with unsubstituted 2-methoxytropone affords azulene through the attack of the nucleophile on the C-2 center (normal pathway). We have observed that 3-substituted 2-methoxytropones undergo steric-guided nucleophilic addition at the C-7 center (abnormal pathway) to afford 5-substituted azulene derivatives. Based on this observation and DFT calculation, a new synthetic strategy is devised for the regioselective synthesis of 5-substituted multifunctional azulenes, which cannot be accessed by any other method.
Collapse
Affiliation(s)
- Neha Rani Kumar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, Nadia, West Bengal, India
| | - Abhijeet R Agrawal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, Nadia, West Bengal, India
| | - Sanjio S Zade
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, Nadia, West Bengal, India
| |
Collapse
|
6
|
Robertson SD, Uzelac M, Mulvey RE. Alkali-Metal-Mediated Synergistic Effects in Polar Main Group Organometallic Chemistry. Chem Rev 2019; 119:8332-8405. [DOI: 10.1021/acs.chemrev.9b00047] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Stuart D. Robertson
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, U.K
| | - Marina Uzelac
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, U.K
| | - Robert E. Mulvey
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, U.K
| |
Collapse
|
7
|
Cao F, Orth C, Donlin MJ, Adegboyega P, Meyers MJ, Murelli RP, Elagawany M, Elgendy B, Tavis JE. Synthesis and Evaluation of Troponoids as a New Class of Antibiotics. ACS OMEGA 2018; 3:15125-15133. [PMID: 30533576 PMCID: PMC6275967 DOI: 10.1021/acsomega.8b01754] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/19/2018] [Indexed: 05/11/2023]
Abstract
Novel antibiotics are urgently needed. The troponoids [tropones, tropolones, and α-hydroxytropolones (α-HT)] can have anti-bacterial activity. We synthesized or purchased 92 troponoids and evaluated their antibacterial activities against Staphylococcus aureus, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa. Preliminary hits were assessed for minimum inhibitory concentrations (MIC80) and cytotoxicity (CC50) against human hepatoma cells. Sixteen troponoids inhibited S. aureus/E. coli/A. baumannii growth by ≥80% growth at <30 μM with CC50 values >50 μM. Two selected tropolones (63 and 285) inhibited 18 methicillin-resistant S. aureus (MRSA) strains with similar MIC80 values as against a reference strain. Two selected thiotropolones (284 and 363) inhibited multidrug-resistant (MDR) E. coli with MIC80 ≤30 μM. One α-HT (261) inhibited MDR-A. baumannii with MIC80 ≤30 μM. This study opens new avenues for development of novel troponoid antibiotics to address the critical need to combat MDR bacterial infections.
Collapse
Affiliation(s)
- Feng Cao
- John
Cochran Division, Department of Veterans Affairs Medical Center, 915 North Grand Blvd., St. Louis, Missouri 63106, United States
- E-mail: . Phone: +1 (314) 289-6358. Fax: +1(314) 289-7920 (F.C.)
| | - Cari Orth
- John
Cochran Division, Department of Veterans Affairs Medical Center, 915 North Grand Blvd., St. Louis, Missouri 63106, United States
| | - Maureen J. Donlin
- Edward
A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, United States
| | - Patrick Adegboyega
- John
Cochran Division, Department of Veterans Affairs Medical Center, 915 North Grand Blvd., St. Louis, Missouri 63106, United States
| | - Marvin J. Meyers
- Department
of Chemistry, Saint Louis University, St. Louis, Missouri 63104, United States
| | - Ryan P. Murelli
- Department
of Chemistry, Brooklyn College, The City
University of New York, Brooklyn, New York 11210, United States
- PhD
Program in Chemistry, The Graduate Center
of The City University of New York, New York 10016, United
States
| | - Mohamed Elagawany
- Center for
Clinical Pharmacology, Washington University
School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
- Department
of Pharmaceutical Chemistry, Faculty of Pharmacy, Damanhour University, Damanhour 31111, Egypt
| | - Bahaa Elgendy
- Center for
Clinical Pharmacology, Washington University
School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
- Chemistry
Department, Faculty of Science, Benha University, Benha 13518, Egypt
| | - John E. Tavis
- Department
of Molecular Microbiology and Immunology, The Saint Louis University Liver Center, Saint Louis University School
of Medicine, St. Louis, Missouri 63104, United
States
| |
Collapse
|
8
|
Cao Q, Howard JL, Wheatley E, Browne DL. Mechanochemical Activation of Zinc and Application to Negishi Cross-Coupling. Angew Chem Int Ed Engl 2018; 57:11339-11343. [PMID: 30015403 PMCID: PMC6220771 DOI: 10.1002/anie.201806480] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Indexed: 11/26/2022]
Abstract
A form independent activation of zinc, concomitant generation of organozinc species and engagement in a Negishi cross-coupling reaction via mechanochemical methods is reported. The reported method exhibits a broad substrate scope for both C(sp3 )-C(sp2 ) and C(sp2 )-C(sp2 ) couplings and is tolerant to many important functional groups. The method may offer broad reaching opportunities for the in situ generation organometallic compounds from base metals and their concomitant engagement in synthetic reactions via mechanochemical methods.
Collapse
Affiliation(s)
- Qun Cao
- School of ChemistryCardiff UniversityMain Building, Park PlaceCardiffCF10 3EQUK
| | - Joseph L. Howard
- School of ChemistryCardiff UniversityMain Building, Park PlaceCardiffCF10 3EQUK
| | - Emilie Wheatley
- School of ChemistryCardiff UniversityMain Building, Park PlaceCardiffCF10 3EQUK
| | - Duncan L. Browne
- School of ChemistryCardiff UniversityMain Building, Park PlaceCardiffCF10 3EQUK
| |
Collapse
|
9
|
Cao Q, Howard JL, Wheatley E, Browne DL. Mechanochemical Activation of Zinc and Application to Negishi Cross-Coupling. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806480] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Qun Cao
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff CF10 3EQ UK
| | - Joseph L. Howard
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff CF10 3EQ UK
| | - Emilie Wheatley
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff CF10 3EQ UK
| | - Duncan L. Browne
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff CF10 3EQ UK
| |
Collapse
|
10
|
Ziegler DS, Greiner R, Lumpe H, Kqiku L, Karaghiosoff K, Knochel P. Directed Zincation or Magnesiation of the 2-Pyridone and 2,7-Naphthyridone Scaffold Using TMP Bases. Org Lett 2018; 19:5760-5763. [PMID: 29039957 DOI: 10.1021/acs.orglett.7b02690] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A regioselective zincation of the 2-pyridone and 2,7-naphthyridone scaffolds has been developed. Zincations of the methoxyethoxymethyl (MEM)-protected compounds using TMP2Zn·2MgCl2·2LiCl (TMP = 2,2,6,6-tetramethylpiperidyl) followed by trapping with electrophiles provided functionalized 2-pyridones and 2,7-naphthyridones. I/Mg exchange of iodinated 2-pyridone and 2,7-naphthyridone using i-PrMgCl·LiCl afforded magnesiated intermediates that reacted with electrophiles. A second magnesiation of the 2-pyridone scaffold was achieved by using TMPMgCl·LiCl. Additionally, we report CoCl2-catalyzed cross-couplings of the 1-chloro-2,7-naphthyridines with arylzinc halides.
Collapse
Affiliation(s)
- Dorothée S Ziegler
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| | - Robert Greiner
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| | - Henning Lumpe
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| | - Laura Kqiku
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| | - Konstantin Karaghiosoff
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| | - Paul Knochel
- Department of Chemistry, Ludwig-Maximilians-University Munich , Butenandtstr. 5-13, 81377 Munich, Germany
| |
Collapse
|
11
|
Fused Systems Based on 2-Aminopyrimidines: Synthesis Combining Deprotolithiation-in situ Zincation withN-Arylation Reactions and Biological Properties. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|