1
|
Latha AT, Swamy PCA. Unveiling the Reactivity of Part Per Million Levels of Cobalt-Salen Complexes in Hydrosilylation of Ketones. Chemistry 2024:e202401841. [PMID: 38853149 DOI: 10.1002/chem.202401841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 06/06/2024] [Accepted: 06/09/2024] [Indexed: 06/11/2024]
Abstract
A series of air-stable cobalt(III)salen complexes Co-1 to Co-4 have been synthesized and employed in the hydrosilylation of ketones. Notably, the most intricately tailored Co-3 pre-catalyst exhibited exceptional catalytic activity under mild reaction conditions. The developed catalytic hydrosilylation protocol proceeded with an unusual ppm level (5 ppm) catalyst loading of Co-3 and achieved a maximum turnover number (TON) of 200,000. A wide variety of aromatic, aliphatic, and heterocyclic ketones encompassing both electron-donating and electron-withdrawing substituents were successfully transformed into the desired silyl ethers or secondary alcohols in moderate to excellent yields.
Collapse
Affiliation(s)
- Anjima T Latha
- Main Group Organometallics Optoelectronic Materials and Catalysis Laboratory, Department of Chemistry, National Institute of Technology, Calicut, 673601, India
| | - P Chinna Ayya Swamy
- Main Group Organometallics Optoelectronic Materials and Catalysis Laboratory, Department of Chemistry, National Institute of Technology, Calicut, 673601, India
| |
Collapse
|
2
|
Schiltz P, Casaretto N, Bourcier S, Auffrant A, Gosmini C. Phosphinoquinoline supported Co II, Ni II, and Fe II complexes: divergent behaviour upon reduction. Dalton Trans 2023; 52:14859-14866. [PMID: 37792445 DOI: 10.1039/d3dt02441e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The reduction of [CoLBr2], a CoII complex supported by a diisopropylphosphinoquinoline (L) ligand, induced a ligand coupling giving access to a (PNNP) supported CoII complex which was isolated in 70% yield. This complex was formed using a minimum of 2 equivalents of a reductant (either Mn or KC8). The fate of [CoLBr2] in the presence of 1 equivalent of a reductant was more difficult to study; nevertheless, a CoI complex was characterised in the solid state. In order to determine whether this ligand coupling could occur with other 3d metals, L supported FeII and NiII complexes were synthesised. While no compound could be identified upon reduction of [FeLBr2], both [NiLBr2] and [NiL2Br](Br) led to the reduction at the metal center allowing the isolation of an original Ni0 trimer in a satisfactory yield. This study shows the different behaviours of these 3d metal complexes in the presence of a reductant.
Collapse
Affiliation(s)
- Pauline Schiltz
- Laboratoire de Chimie Moléculaire (LCM), CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France.
| | - Nicolas Casaretto
- Laboratoire de Chimie Moléculaire (LCM), CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France.
| | - Sophie Bourcier
- Laboratoire de Chimie Moléculaire (LCM), CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France.
| | - Audrey Auffrant
- Laboratoire de Chimie Moléculaire (LCM), CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France.
| | - Corinne Gosmini
- Laboratoire de Chimie Moléculaire (LCM), CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France.
| |
Collapse
|
3
|
Fan Q, Du X, Yang W, Li Q, Huang W, Sun H, Hinz A, Li X. Effects of silylene ligands on the performance of carbonyl hydrosilylation catalyzed by cobalt phosphine complexes. Dalton Trans 2023; 52:6712-6721. [PMID: 37129049 DOI: 10.1039/d3dt00372h] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In order to study the effects of silylene ligands on the catalytic activity of carbonyl hydrosilylation catalyzed by cobalt phosphine complexes, readily available model catalysts are required. In this contribution, a comparative study of the hydrosilylation of aldehydes and ketones catalyzed by tris(trimethylphosphine) cobalt chloride, CoCl(PMe3)3 (1), and bis(silylene) cobalt chloride, Co(LSi:)2(PMe3)2Cl (2, LSi: = {PhC(NtBu)2}SiCl), is presented. It was found that both complexes 1 and 2 are good catalysts for the hydrosilylation of aldehydes and ketones under mild conditions. This catalytic system has a broad substrate scope and selectivity for multi-functional substrates. Silylene complex 2 shows higher activity than complex 1, bearing phosphine ligands, for aldehydes, but conversely, for ketones, the activity of complex 1 is higher than that of complex 2. It is worth noting that in the process of mechanistic studies the intermediates (PMe3)3Co(H)(Cl)(PhH2Si) (3) and (LSi:)2(PMe3)Co(H)(Cl)(PhH2Si) (4) were isolated from the stoichiometric reactions of 1 and 2 with phenylsilane, respectively. Further experiments confirmed that complex 3 is a real intermediate. A possible catalytic mechanism for the hydrosilylation of carbonyl compounds catalyzed by 1 was proposed based on the experimental investigation and literature reports, and this mechanism was further supported by DFT studies. The bis(silylene) complex 4 showed complicated behavior in solution. A series of experiments were designed to study the catalytic mechanism for the hydrosilylation of carbonyl compounds catalyzed by complex 2. According to the experimental results, the hydrosilylation of aldehydes catalyzed by 1 proceeds via a different mechanism than that of the analogous reaction with complex 2 as the catalyst. In the case of ketones, complex 4 is a real intermediate, indicating that both 1 and 2 catalyze the reaction by the same mechanism. The molecular structures of 3 and 4 were determined by single crystal X-ray diffraction analysis.
Collapse
Affiliation(s)
- Qingqing Fan
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Xinyu Du
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Wenjing Yang
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Qingshuang Li
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Wei Huang
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Hongjian Sun
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| | - Alexander Hinz
- Karlsruher Institut für Technologie (KIT), Institute for Inorganic Chemistry (AOC), Engesserstr. 15, 76131 Karlsruhe, Germany.
| | - Xiaoyan Li
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250100 Jinan, People's Republic of China.
| |
Collapse
|
4
|
Sharma A, So S, Kim JH, MacMillan SN, Baik MH, Trovitch RJ. An Aryl Diimine Cobalt(I) Catalyst for Carbonyl Hydrosilylation. Chem Commun (Camb) 2022; 58:10793-10796. [DOI: 10.1039/d2cc04089a] [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
Through the application of a redox-innocent aryl diimine chelate, the discovery and utilization of a cobalt catalyst, (Ph2PPrADI)Co, that exhibits carbonyl hydrosilylation turnover frequencies of up to 330 s–1 is...
Collapse
|