1
|
Li F, Kong YC, Yang Z, Wang C. Lanthanide (Substituted-)Cyclopentadienyl Bis(phosphinimino)methanediide Complexes: Synthesis and Characterization. ACS OMEGA 2024; 9:50830-50837. [PMID: 39741868 PMCID: PMC11683641 DOI: 10.1021/acsomega.4c09784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2024] [Revised: 11/20/2024] [Accepted: 11/27/2024] [Indexed: 01/03/2025]
Abstract
Design and synthesis of high-performance single-molecule magnets (SMMs) have long been a research focus. Inspired by the best dysprosium(III) metallocene SMMs and dysprosium(III) bis(methanediide) SMMs, we assumed dysprosium SMMs, which had electrical neutrality by combining the two types of ligands. As the Dy3+ center is coordinated by one (substituted-)cyclopentadienyl (CpR) ligand and one methanediide ({C(PPh2NSiMe3)2}2-) ligand on the axial sites, this ideal structure with linear Ccarbene-Dy-Cpcent would strengthen the magnetic anisotropy and exhibit excellent SMM properties. However, it is not easy to synthesize it in this configuration. We for the first time obtained [Y{C(PPh2NSiMe3)2}(CpR)(THF)] (CpR = Cp(1), Cp tBu(2), Cp*(3), Cp = C5H5, Cp tBu = C5H4 tBu, Cp* = C5Me5) through the reactions of NaCp/KCpR and [Y{C(PPh2NSiMe3)2}(I)(THF)2]. In the molecular structures of 1-3, except for the two expected ligands, one coordination tetrahydrofuran (THF) molecule was also found in each complex. The P-C-P values of 1-3 were 135.46(7), 136.421(8), and 131.43(10)°, respectively, which were far less than 180°. The Ccarbene-Y-Cpcent of 1-3 deviated significantly from the linear shape, which was 118.021, 129.459, and 118.331°, respectively. Such a coordination environment makes the dysprosium congener [Dy{C(PPh2NSiMe3)2}(Cp*)(THF)] (4) whose Ccarbene-Dy-Cpcent (118.295°) was too small to maintain axiality and which almost exhibited no SMM properties. Even though the first exploration of lanthanide (substituted-)cyclopentadienyl bis(phosphinimino)methanediide complexes did not live up to our expectation, it provided great experiences for the future success of high-performance lanthanide (substituted-)cyclopentadienyl methanediide SMMs.
Collapse
Affiliation(s)
- Fan Li
- School of Chemistry, Chemical
Engineering and Life Science, Wuhan University
of Technology, 122 Luoshi Road, Wuhan 430070, Hubei, P. R. China
| | - Yin-Cong Kong
- School of Chemistry, Chemical
Engineering and Life Science, Wuhan University
of Technology, 122 Luoshi Road, Wuhan 430070, Hubei, P. R. China
| | - Zi Yang
- School of Chemistry, Chemical
Engineering and Life Science, Wuhan University
of Technology, 122 Luoshi Road, Wuhan 430070, Hubei, P. R. China
| | - Chen Wang
- School of Chemistry, Chemical
Engineering and Life Science, Wuhan University
of Technology, 122 Luoshi Road, Wuhan 430070, Hubei, P. R. China
| |
Collapse
|
2
|
Jiang H, Jin K, Lin X, Yu M, Xiao X, Huang X. Selective 1,1- and 1,2-dibromination of phenylethanes in the presence of NaBr/NaBrO 3/H 2SO 4 as the bromination reagent. Org Biomol Chem 2024; 22:6960-6965. [PMID: 39136068 DOI: 10.1039/d4ob01016g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2024]
Abstract
Selective 1,1- and 1,2-dibromination of phenylethanes by simply adjusting the reaction conditions has been developed. Mixtures of NaBr/NaBrO3/H2SO4 are employed as green bromination reagents, which can release Br2 or BrOH in situ as required without polluting the environment. Both the resulting 1,1- and 1,2-dibromoethyl arenes can be easily transformed to phenylacetylenes via elimination under basic conditions, demonstrating great potential for industrial applications.
Collapse
Affiliation(s)
- Haohao Jiang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| | - Kaidi Jin
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| | - Xia Lin
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| | - Mengzhao Yu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| | - Xiaohui Xiao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| | - Xiaolei Huang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
| |
Collapse
|
3
|
Degroote F, Denoo B, Ryckaert B, Callebaut B, Van Hecke K, Hullaert J, Winne JM. Dithioallyl cation (3 + 2) cycloadditions under aprotic reaction conditions: rapid access to spiro-fused cyclopentane scaffolds. Org Biomol Chem 2023; 21:8117-8124. [PMID: 37786324 DOI: 10.1039/d3ob01273e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
We report a general method to effect all-carbon (3 + 2) cycloadditions that can elaborate cyclopentenes from a range of olefins. The required dithioallyl cation reagents can be generated in a newly developed mild protocol starting from 2-allyloxypyridine precursors, thus avoiding the use of strong Brønsted acids. The novel method significantly expands the substrate scope, which now also includes acid-sensitive olefins, and thus enables the preparation of previously inaccessible spiro-fused scaffold types from simple and readily available starting materials.
Collapse
Affiliation(s)
- Frederick Degroote
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| | - Bram Denoo
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| | - Bram Ryckaert
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| | - Brenda Callebaut
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| | - Kristof Van Hecke
- XStruct, Department of Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent, Belgium
| | - Jan Hullaert
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| | - Johan M Winne
- OSgroup, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Ghent, Belgium.
| |
Collapse
|
4
|
Ryckaert B, Demeyere E, Degroote F, Janssens H, Winne JM. 1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures. Beilstein J Org Chem 2023; 19:115-132. [PMID: 36761474 PMCID: PMC9907017 DOI: 10.3762/bjoc.19.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/20/2023] [Indexed: 02/05/2023] Open
Abstract
This review covers the synthetic applications of 1,4-dithianes, as well as derivatives thereof at various oxidation states. The selected examples show how the specific heterocyclic reactivity can be harnessed for the controlled synthesis of carbon-carbon bonds. The reactivity is compared to and put into context with more common synthetic building blocks, such as 1,3-dithianes and (hetero)aromatic building blocks. 1,4-Dithianes have as yet not been investigated to the same extent as their well-known 1,3-dithiane counterparts, but they do offer attractive transformations that can find good use in the assembly of a wide array of complex molecular architectures, ranging from lipids and carbohydrates to various carbocyclic scaffolds. This versatility arises from the possibility to chemoselectively cleave or reduce the sulfur-heterocycle to reveal a versatile C2-synthon.
Collapse
Affiliation(s)
- Bram Ryckaert
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 (S4), 9000 Gent, Belgium
| | - Ellen Demeyere
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 (S4), 9000 Gent, Belgium
| | - Frederick Degroote
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 (S4), 9000 Gent, Belgium
| | - Hilde Janssens
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 (S4), 9000 Gent, Belgium
| | - Johan M Winne
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 (S4), 9000 Gent, Belgium
| |
Collapse
|
5
|
Ryckaert B, Hullaert J, Van Hecke K, Winne JM. Dearomative (3 + 2) Cycloadditions of Unprotected Indoles. Org Lett 2022; 24:4119-4123. [PMID: 35674713 DOI: 10.1021/acs.orglett.2c01214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The (3 + 2) cycloaddition of various indoles with a dithioallyl cation affords dearomatized cyclopentannulated adducts, with complete control of regioselectivity and excellent chemo- and diastereoselectivity. The success of the reaction critically relies on the use of an excess of very strong Brønsted acid, which paradoxically prevents carbocationic side reactions. The reaction tolerates sensitive functionalities such as basic amines or free hydroxyls, and we demonstrate its use in late stage derivatization of highly functionalized, unprotected indoles.
Collapse
Affiliation(s)
- Bram Ryckaert
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
| | - Jan Hullaert
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
| | - Kristof Van Hecke
- Department of Chemistry, Ghent University, Krijgslaan 281-S3, B-9000 Ghent, Belgium
| | - Johan M Winne
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, B-9000 Ghent, Belgium
| |
Collapse
|
6
|
Lam H, Lautens M, Abel-Snape X, Köllen MF. Recent Advances in Transition-Metal-Free (4+3)-Annulations. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/s-0040-1706023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract(4+3)-Annulations are incredibly versatile reactions which combine a 4-atom synthon and a 3-atom synthon to form both 7-membered carbocycles as well as heterocycles. We have previously reviewed transition-metal-catalyzed (4+3)-annulations. In this review, we will cover examples involving bases, NHCs, phosphines, Lewis and Brønsted acids as well as some rare examples of boronic acid catalysis and photocatalysis. In analogy to our previous review, we exclude annulations involving cyclic dienes like furan, pyrrole, cyclohexadiene or cyclopentadiene, as Chiu, Harmata, Fernándes and others have recently published reviews encompassing such substrates. We will however discuss the recent additions (2010–2020) to the literature on (4+3)-annulations involving other types of 4-atom-synthons.1 Introduction2 Bases3 Annulations Using N-Heterocyclic Carbenes3.1 N-Heterocyclic Carbenes (NHCs)3.2 N-Heterocyclic Carbenes and Base Dual-Activation4 Phosphines5 Acids5.1 Lewis Acids5.2 Brønsted Acids6 Boronic Acid Catalysis and Photocatalysis7 Conclusion
Collapse
Affiliation(s)
- Heather Lam
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Mark Lautens
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Xavier Abel-Snape
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Martin F. Köllen
- Ludwig-Maximilians-Universität München, Department Chemie und Biochemie
| |
Collapse
|
7
|
Lin X, Fang C, Huang X, Xiao X. 1,1,2-Tribromoethyl arenes: novel and highly efficient precursors for the synthesis of 1-bromoalkynes and α-bromoketones. Org Chem Front 2021. [DOI: 10.1039/d1qo00793a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel tribromination method to prepare versatile intermediate 1,1,2-tribromoethyl arenes, which can not only be transformed to synthetically valuable 1-bromoalkynes via elimination but also be hydrolyzed to a variety of α-bromoketones, was developed.
Collapse
Affiliation(s)
- Xia Lin
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials
- Department of Chemistry
- Zhejiang Normal University
- Jinhua
- China
| | - Chengtao Fang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials
- Department of Chemistry
- Zhejiang Normal University
- Jinhua
- China
| | - Xiaolei Huang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials
- Department of Chemistry
- Zhejiang Normal University
- Jinhua
- China
| | - Xiaohui Xiao
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials
- Department of Chemistry
- Zhejiang Normal University
- Jinhua
- China
| |
Collapse
|