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Mondal S, Sarkar S, Mandal C, Mallick D, Mukherjee D. Fluorenyl-tethered N-heterocyclic carbene (NHC): an exclusive C-donor ligand for heteroleptic calcium and strontium chemistry. Chem Commun (Camb) 2024; 60:4553-4556. [PMID: 38568715 DOI: 10.1039/d4cc00397g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2024]
Abstract
Exclusive C-donating ligands are rarely used with kinetically labile heavier alkaline earths (Ca, Sr, Ba). We report herein the aptitude of a combination of NHC with fluorenyl connected by a flexible -(CH2)2- linker as a ligand support for heteroleptic Ca- and Sr-N(SiMe3)2 and iodides. The Ca-N(SiMe3)2 complex even catalyzes the intramolecular hydroamination of aminoalkenes to showcase the effectiveness of this ligand framework.
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Affiliation(s)
- Sumana Mondal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, 741246, West Bengal, India.
| | - Subham Sarkar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, 741246, West Bengal, India.
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata, West Bengal, 700073, India.
| | - Chhotan Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, 741246, West Bengal, India.
| | - Dibyendu Mallick
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata, West Bengal, 700073, India.
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, 741246, West Bengal, India.
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Saliyeva LM, Dyachenko IV, Danyliuk IY, Vovk MV. Di-, tetra-, and perhydropyrrolo[1,2- a]imidazoles: The Methods of Synthesis and Some Aspects of Application. Chem Heterocycl Compd (N Y) 2023; 58:661-680. [PMID: 36687505 PMCID: PMC9838525 DOI: 10.1007/s10593-023-03142-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 08/03/2022] [Indexed: 01/13/2023]
Abstract
The review summarizes and systematizes the literature data on the synthesis and some aspects of application of pyrrolo[1,2-a]imidazoles. Synthetic approaches are grouped according to the degree of saturation of the product pyrroloimidazole ring. The bibliography of the review includes 110 sources over the last 15 years.
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Affiliation(s)
- Lesya M. Saliyeva
- Lesya Ukrainka Volyn National University, 13 Voli Ave, Lutsk, 43025 Ukraine
| | - Irina V. Dyachenko
- Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, 3001 12e Nord Ave., Sherbrooke, Quebec J1H 5N4 Canada
| | - Ivanna Yu. Danyliuk
- Institute of Organic Chemistry, National Academy of Sciences of Ukraine, 5 Akademika Kukhara St, Kyiv, 02094 Ukraine
| | - Mykhailo V. Vovk
- Institute of Organic Chemistry, National Academy of Sciences of Ukraine, 5 Akademika Kukhara St, Kyiv, 02094 Ukraine
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Baguli S, Das S, Chakraborty M, Goswami S, Datta A, Mukherjee D. [(Flu)-(CH 2) 2-(NHC)-CH 2-(NHC)-(CH 2) 2-(Flu)] 2−: an ‘all-organic’ hybrid and flexible ligand that enwraps a Ca 2+ pseudo-tetrahedrally. Chem Commun (Camb) 2022; 58:12188-12191. [DOI: 10.1039/d2cc04700d] [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 conformationally flexible ligand, [(Flu)-(CH2)2-(NHC)-CH2-(NHC)-(CH2)2-(Flu)]2− (L), that offers four sequential organic donor modules and enwraps a Ca2+ pseudo-tetrahedrally in a twisted ‘S’-shape is devised.
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Affiliation(s)
- Sudip Baguli
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Shovan Das
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja SC Mallick Road, Jadavpur, Kolkata, 700032, India
| | - Mahua Chakraborty
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Santu Goswami
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Ayan Datta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja SC Mallick Road, Jadavpur, Kolkata, 700032, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India
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Evans KJ, Morton PA, Luz C, Miller C, Raine O, Lynam JM, Mansell SM. Rhodium Indenyl NHC and Fluorenyl-Tethered NHC Half-Sandwich Complexes: Synthesis, Structures and Applications in the Catalytic C-H Borylation of Arenes and Alkanes. Chemistry 2021; 27:17824-17833. [PMID: 34653269 PMCID: PMC9299238 DOI: 10.1002/chem.202102961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Indexed: 01/11/2023]
Abstract
Indenyl (Ind) rhodium N-heterocyclic carbene (NHC) complexes [Rh(η5 -Ind)(NHC)(L)] were synthesised for 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene (SIPr) with L=C2 H4 (1), CO (2 a) and cyclooctene (COE; 3), for 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene (SIMes) with L=CO (2 b) and COE (4), and 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) with L=CO (2 c) and COE (5). Reaction of SIPr with [Rh(Cp*)(C2 H4 )2 ] did not give the desired SIPr complex, thus demonstrating the "indenyl effect" in the synthesis of 1. Oxidative addition of HSi(OEt)3 to 3 proceeded under mild conditions to give the Rh silyl hydride complex [Rh(Ind){Si(OEt)3 }(H)(SIPr)] (6) with loss of COE. Tethered-fluorenyl NHC rhodium complexes [Rh{(η5 -C13 H8 )C2 H4 N(C)C2 Hx NR}(L)] (x=4, R=Dipp, L=C2 H4 : 11; L=COE: 12; L=CO: 13; R=Mes, L=COE: 14; L=CO: 15; x=2, R=Me, L=COE: 16; L=CO: 17) were synthesised in low yields (5-31 %) in comparison to good yields for the monodentate complexes (49-79 %). Compounds 3 and 1, which contain labile alkene ligands, were successful catalysts for the catalytic borylation of benzene with B2 pin2 (Bpin=pinacolboronate, 97 and 93 % PhBpin respectively with 5 mol % catalyst, 24 h, 80 °C), with SIPr giving a more active catalyst than SIMes or IMes. Fluorenyl-tethered NHC complexes were much less active as borylation catalysts, and the carbonyl complexes were inactive. The borylation of toluene, biphenyl, anisole and diphenyl ether proceeded to give meta substitutions as the major product, with smaller amounts of para substitution and almost no ortho product. The borylation of octane and decane with B2 pin2 at 120 and 140 °C, respectively, was monitored by 11 B NMR spectroscopy, which showed high conversions into octyl and decylBpin over 4-7 days, thus demonstrating catalysed sp3 C-H borylation with new piano stool rhodium indenyl complexes. Irradiation of the monodentate complexes with 400 or 420 nm light confirmed the ready dissociation of C2 H4 and COE ligands, whereas CO complexes were inert. Evidence for C-H bond activation in the alkyl groups of the NHC ligands was obtained.
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Affiliation(s)
- Kieren J Evans
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Paul A Morton
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Christian Luz
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Callum Miller
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Olivia Raine
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Jason M Lynam
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - Stephen M Mansell
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
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Evans KJ, Morton PA, Sangster C, Mansell SM. One-step synthesis of heteroleptic rare-earth amide complexes featuring fluorenyl-tethered N-heterocyclic carbene ligands. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Evans KJ, Mansell SM. Functionalised N-Heterocyclic Carbene Ligands in Bimetallic Architectures. Chemistry 2020; 26:5927-5941. [PMID: 31981386 PMCID: PMC7317719 DOI: 10.1002/chem.201905510] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Indexed: 12/18/2022]
Abstract
N-Heterocyclic carbenes (NHCs) have become immensely successful ligands in coordination chemistry and homogeneous catalysis due to their strong terminal σ-donor properties. However, by targeting NHC ligands with additional functionalisation, a new area of NHC coordination chemistry has developed that has enabled NHCs to be used to build up bimetallic and multimetallic architectures. This minireview covers the development of functionalised NHC ligands that incorporate additional donor sites in order to coordinate two or more metal atoms. This can be through the N-atom of the NHC ring, through a donor group attached to the N-atom or the carbon backbone, coordination of the π-bond or an annulated π-donor on the backbone, or through direct metalation of the backbone.
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Affiliation(s)
- Kieren J. Evans
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
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Bischof T, Evans KJ, Haddow MF, Mansell SM. An indenide-tethered N-heterocyclic stannylene. Acta Crystallogr E Crystallogr Commun 2020; 76:254-256. [PMID: 32071756 PMCID: PMC7001827 DOI: 10.1107/s205698902000047x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/14/2020] [Indexed: 11/19/2022]
Abstract
The structure of (μ-1κN:2(η2),κ2 N,N'-(2-{[2,6-bis(propan-2-yl)phen-yl]aza-nid-yl}eth-yl)[2-(1H-inden-1-yl)eth-yl]aza-nido)(1,4,7,10,13,16-hexa-oxa-cyclo-octa-dec-ane-1κ6 O)lithiumtin, [LiSn(C8H16O4)(C25H31N2)], at 100 K has monoclinic (P21/n) symmetry. Analysis of the coordination of the Sn to the indenyl ring shows that the Sn inter-acts in an η2 fashion. A database survey showed that whilst this coordination mode is unusual for Ge and Pb compounds, Sn displays a wider range of coordination modes to cyclo-penta-dienyl ligands and their derivatives.
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Affiliation(s)
- Tobias Bischof
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, Scotland
| | - Kieren J. Evans
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, Scotland
| | - Mairi F. Haddow
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, Scotland
| | - Stephen M. Mansell
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, Scotland
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Evans KJ, Campbell CL, Haddow MF, Luz C, Morton PA, Mansell SM. Lithium Complexes with Bridging and Terminal NHC Ligands: The Decisive Influence of an Anionic Tether. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201901003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Kieren J. Evans
- Institute of Chemical Sciences Heriot‐Watt University EH14 4AS Edinburgh UK
| | | | - Mairi F. Haddow
- Institute of Chemical Sciences Heriot‐Watt University EH14 4AS Edinburgh UK
| | - Christian Luz
- Institute of Chemical Sciences Heriot‐Watt University EH14 4AS Edinburgh UK
| | - Paul A. Morton
- Institute of Chemical Sciences Heriot‐Watt University EH14 4AS Edinburgh UK
| | - Stephen M. Mansell
- Institute of Chemical Sciences Heriot‐Watt University EH14 4AS Edinburgh UK
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Evans KJ, Mansell SM. Synergic Deprotonation Generates Alkali-Metal Salts of Tethered Fluorenide-NHC Ligands Co-Complexed to Alkali-Metal Amides. Chemistry 2019; 25:3766-3769. [PMID: 30667554 PMCID: PMC6492165 DOI: 10.1002/chem.201806278] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Indexed: 11/23/2022]
Abstract
Synergic combinations of alkali-metal hydrocarbyl/amide reagents were used to synthesise saturated N-heterocyclic carbene (NHC) ligands tethered to a fluorenide anion through deprotonation of a spirocyclic precursor, whereas conventional bases were not successful. The Li2 derivatives displayed a bridging amide between two Li atoms within the fluorenide-NHC pocket, whereas the Na2 and K2 analogues displayed extended solid-state structures with the fluorenide-NHC ligand chelating one alkali metal centre.
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Affiliation(s)
- Kieren J. Evans
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
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