Efficient solvent-free fixation of CO2 catalyzed by new recyclable bifunctional metal complexes

Peng, Jing; Wang, Sheng; Ban, Binru; Wei, Zidong; Lei, Bo; Guo, Cun‐Yue

doi:10.1016/j.jcou.2017.12.003

Cited by 41 publications

(15 citation statements)

References 103 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The chemistry of zinc complexes has undergone a remarkable renaissance in the past decade. − The renewed interest toward these compounds has mainly arisen from their attractive reactivities − and potential applications in a broad range of reactions, including the hydroboration of alkynes, , the Strecker reaction, the Barbier reaction, the aminophenol oxidation reaction, the C–S cross-coupling reaction, the hydrosilylation of N-heterocycles, the copolymerization of epoxides and CO 2 , − and so forth. , Zinc is an inexpensive, biocompatible, less toxic and earth-abundant metal, which makes it particularly appealing to replace toxic and/or noble-metal complexes in catalytic transformations. Thus, the synthesis of zinc complexes with high catalytic activity is of great importance.…”

Section: Introductionmentioning

confidence: 99%

Zinc Complexes with an Ethylene-Bridged Bis(β-diketiminate) Ligand: Syntheses, Structures, and Applications as Catalysts in the Borylation of Aryl Iodides

Dang

et al. 2021

Organometallics

View full text Add to dashboard Cite

A dinucleating bis(β-diketiminate) ligand with a flexible bridge has been employed to synthesize zinc complexes. The ligand, abbreviated H2L (H2L = N-(4-((2-((4-((2,6-diisopropylphenyl)imino)pent-2-en-2-yl)amino)ethyl)imino)pent-2-en-2-yl)-2,6-diisopropylaniline), was deprotonated with ZnEt2 to afford [LZn2Et2] (1). Reactions of 1 with 2 equiv of BnOH and nBuOH, respectively, gave access to [LZn2(OBn)2]·C6H14 (2·C6H14) and [LZn2(OnBu)2] (3). Treatment of 1 with 2 equiv of I2 in THF produced [LZn2I2(THF)2]·2THF (4·2THF). X-ray single-crystal diffraction analyses revealed that they are all heteroleptic bimetallic compounds with two metal centers being chelated by one ligand set. The structurally similar compounds 1 and 4·2THF possess approximate C 2 symmetry, with two β-diketiminate units being arrayed in head-to-tail antiparallel mode. Thus, the molecular structures of 1 and 4·2THF exhibit a seesaw-like topology. The structures of 2·C6H14 and 3 are almost identical, in which two zinc atoms are shared by two ZnN2C3 six-membered rings, two Zn2ON2C2 seven-membered rings, and one Zn2O2 four-membered ring. Therefore, the metal cores of 2·C6H14 and 3 display a crownlike topology. All complexes are catalytically active for the borylation of aryl iodides with B2Pin2 (B2Pin2 = 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bis(1,3,2-dioxaborolane). Complex 1 shows higher activity in comparison to 2, 3, and 4·2THF. The borylation reactions catalyzed by 1 could proceed under mild conditions and can be applied to a series of substrates with high functional group generality. This methodology thus represents a novel use of β-diketiminate zinc complexes for C–I borylation.

show abstract

Section: Introductionmentioning

confidence: 99%

Zinc Complexes with an Ethylene-Bridged Bis(β-diketiminate) Ligand: Syntheses, Structures, and Applications as Catalysts in the Borylation of Aryl Iodides

Dang

et al. 2021

Organometallics

View full text Add to dashboard Cite

show abstract

“…As an attempt to understand the rate of the reaction, rate eq was simplified to eq , considering the excess use of CO 2 and the concentration of catalyst remains constant during the reaction. The natural logarithm of the rate law (eq ) results in eq , which is possible to afford the order “c” of the reaction with respect to the catalyst concentration by examination of a double logarithmic plot …”

Section: Results and Discussionmentioning

confidence: 99%

Catalytic Conversion of Carbon Dioxide Using Binuclear Double-Stranded Helicates: Cyclic Carbonate from Epoxides and Diol

et al. 2020

View full text Add to dashboard Cite

The construction of sophisticated molecular architectures from chemical subunits requires careful selection of the spacers, precise synthetic strategies, and substantial efforts. Here, we report a series of binuclear double-stranded helicates synthesized from different combinations of pyridyl hydrazone-based multidentate ligands (H2 1, H2 2, H2 3) by increasing the methylene spacer and transition metals (Co, Ni, and Zn). The ligands H2 1 (N′1,N′3-bis((E)-pyridin-2-ylmethylene)malonohydrazide), H2 2 (N′1,N′4-bis((E)-pyridin-2-ylmethylene)succinohydrazide), and H2 3 (N′1,N′5-bis((E)-pyridin-2-ylmethylene)glutarohydrazide) and their respective complexes with Co, Ni, and Zn were obtained. Single-crystal X-ray diffraction studies of these binuclear metallohelicates confirm the double-stranded helical structure of the complexes derived from H2 2. The set of helicates Co-1, Co-2, and Co-3; Ni-1, Ni-2, and Ni-3; and Zn-1, Zn-2, and Zn-3 were investigated for its catalytic activity in the cyclic carbonate formation reaction. Intriguingly, among the synthesized catalyst, Co-1 was found to be better in terms of conversions with the calculated TOF (turnover frequency) of 128/h. The catalytic performance was significantly improved by adding 0.2 mmol of tetrabutylammonium bromide by achieving 76% conversion in 30 min, with the observed TOF of 15,934 h–1/molecule and 7967 h–1/Co center. The results obtained herein show that the double-stranded helicates are effective catalysts for converting both terminal and non-terminal epoxides into their corresponding cyclic carbonates. The striking feature of this catalytic protocol lies in demonstrating the catalytic activity for the conversion of diol to cyclic carbonate, and the detailed kinetic experiments tempted us to propose a tentative reaction mechanism for this conversion.

show abstract

“…The metal‐alkoxide intermediate is quite stable for rapid CO 2 attack, leading to the CO 2 insertion to form the carbonate intermediate. This nucleophilic attack on the carbonate in step 4 facilitate the ring closure and produce the end product as cyclic carbonate as depicted in Scheme …”

Section: Resultsmentioning

confidence: 99%

Bifunctional coordination polymers as efficient catalysts for carbon dioxide conversion

Arunachalam

Chinnaraja

Valkonen

et al. 2019

Applied Organom Chemis

View full text Add to dashboard Cite

The multidentate ligand H 2 L upon complexation with Zn (II) and Cd (II) provide a one-dimensional polymeric networks. These coordination polymers (CPs) CP-1 and CP-2 containing Zn (II) and Cd (II) metals respectively are well characterized. The single crystal structural analysis confirms the formation of one-dimensional coordination polymer with zigzag fashion in CP-1 and ladder chain CP-2. Both the CPs are applied as catalysts to synthesize various cyclic carbonates from epoxides and carbon dioxide. The catalysts are giving better conversion under solvent-free and additive-free condition using 10 bar CO 2 and 100°C as optimized pressure and temperature. The detailed kinetic experiments suggesting the first order kinetics, the energy of activation (Ea) is calculated for this catalytic conversion.

show abstract

Efficient solvent-free fixation of CO2 catalyzed by new recyclable bifunctional metal complexes

Cited by 41 publications

References 103 publications

Zinc Complexes with an Ethylene-Bridged Bis(β-diketiminate) Ligand: Syntheses, Structures, and Applications as Catalysts in the Borylation of Aryl Iodides

Zinc Complexes with an Ethylene-Bridged Bis(β-diketiminate) Ligand: Syntheses, Structures, and Applications as Catalysts in the Borylation of Aryl Iodides

Catalytic Conversion of Carbon Dioxide Using Binuclear Double-Stranded Helicates: Cyclic Carbonate from Epoxides and Diol

Bifunctional coordination polymers as efficient catalysts for carbon dioxide conversion

Contact Info

Product

Resources

About