Alternating copolymerization of carbon dioxide and propylene oxide under bifunctional cobalt salen complexes: Role of Lewis base substituent covalent bonded on salen ligand

2009 ◽  
Vol 48 (2) ◽  
pp. 359-365 ◽  
Author(s):  
Binyuan Liu ◽  
Yanhao Gao ◽  
Xin Zhao ◽  
Weidong Yan ◽  
Xianhong Wang
Keyword(s):  
Carbon Dioxide ◽  
Propylene Oxide ◽  
Lewis Base ◽  
Salen Complexes ◽  
Alternating Copolymerization ◽  
Salen Ligand

Alternating copolymerization of carbon dioxide and propylene oxide by single-component cobalt salen complexes with various axial group

Polymer ◽  
2009 ◽  
Vol 50 (21) ◽  
pp. 5071-5075 ◽  
Author(s):  
Binyuan Liu ◽  
Xin Zhao ◽  
Hongfei Guo ◽  
Yanhao Gao ◽  
Min Yang ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Propylene Oxide ◽  
Single Component ◽  
Salen Complexes ◽  
Alternating Copolymerization

Chiral salenCo(iii) complexes with bulky substituents as catalysts for stereoselective alternating copolymerization of racemic propylene oxide with carbon dioxide and succinic anhydride

2021 ◽  
Vol 12 (12) ◽  
pp. 1776-1786
Author(s):  
Zhou Wang ◽  
Ying Mu
Keyword(s):  
Carbon Dioxide ◽  
Propylene Carbonate ◽  
Propylene Oxide ◽  
Succinic Anhydride ◽  
Poly Propylene ◽  
Alternating Copolymerization

Stereoregular poly(propylene carbonate)s and poly(propylene succinate-block-carbonate)s were synthesized with new chiral salenCo(iii) catalysts carrying bulky substituents.

scholarly journals Tertiary Amines Paired with Trialkyl Boranes: A Simple Organocatalyst for Fully Alternating Copolymerization of Carbon Dioxide and Propylene Oxide

2020 ◽  
Author(s):  
Xing-Hong Zhang
Keyword(s):  
Carbon Dioxide ◽  
Small Molecules ◽  
Propylene Oxide ◽  
Average Molecular Weight ◽  
Tertiary Amines ◽  
Carbon Dioxide Co2 ◽  
Poly Propylene ◽  
Alternating Copolymerization ◽  
Completely Alternating ◽  
Huge Challenge

Metal-free synthesis of fully alternating polycarbonates from carbon dioxide (CO2) and epoxides is highly desired but a huge challenge. Here, we disclose the combination of tertiary amines with trialkyl boranes for completely alternating copolymerization of CO2 with epoxides. Triethylamine (TEA) pairing with triethyl borane (TEB), the simplest catalyst for the copolymerization of CO2 and propylene oxide (PO), afforded fully alternating poly(propylene carbonate) (PPC) with a turnover frequency (TOF) of 54 h-1 at 60 oC. Remarkably, diamine such as, N,N,N',N'-tetraethylethylenediamine (TEED) and triamine such as N,N,N',N'',N''-pentamethyldiethylene triamine (PMDETA) pairing with TEB exhibited improved the copolymer selectivity of up to 99%. Supplementally, the effect of trialkylborane structure on the copolymerization were also investigated. Moreover, PPCs prepared from these tertiary amines/ trialkyl boranes Lewis pairs showed the head-to-tail diad content of around 80%. The number-average molecular weight of PPC was up to 56.0 kg/mol with narrow distribution (Đ =1.16) and could be easily adjusted by simply varying the feeding ratios. The 1H NMR spectra and MALDI-TOF-MS spectra suggest that both tertiary amine-activating CO2 and TEB-masked end anions cooperatively promote the fully alternating CO2/epoxide copolymerization. This work provides an organocatalytic platform for well-defined CO2/epoxide copolymers using simple small molecules with high atomic utilization.<br>

Salen ligand complexes as electrocatalysts for direct electrochemical reduction of gaseous carbon dioxide to value added products

RSC Advances ◽  
2015 ◽  
Vol 5 (5) ◽  
pp. 3581-3589 ◽  
Author(s):  
Surya Singh ◽  
Bedika Phukan ◽  
Chandan Mukherjee ◽  
Anil Verma
Keyword(s):  
Carbon Dioxide ◽  
Electrochemical Reduction ◽  
Value Added ◽  
Salen Complexes ◽  
Gaseous Carbon Dioxide ◽  
Salen Ligand ◽  
Centrosymmetric Molecule ◽  
Value Added Products

CO2, being a linear and centrosymmetric molecule, is very stable, and the electrochemical reduction of CO2 requires energy. However, the salen complexes are found to be very efficient to minimize overpotential as compared to their metal counterparts.

Copolymerization of Carbon Dioxide and Propylene Oxide Catalyzed by Salen Complexes

2013 ◽  
Vol 734-737 ◽  
pp. 2159-2162 ◽  
Author(s):  
Chong Wen Jiang ◽  
Chen Chen Zhao ◽  
Ke Yuan Zhou
Keyword(s):  
Carbon Dioxide ◽  
1H Nmr ◽  
Propylene Oxide ◽  
Great Influence ◽  
Carbonate Content ◽  
Central Metal ◽  
Salen Complexes ◽  
Metal Atoms ◽  
Ft Ir

Three salen complexes N,N'-bis(salicylidene)-1,2-phenylenediamino MⅢ Cl were prepared and employed for the copolymerization of carbon dioxide with propylene oxide. FT-IR and UV-Vis spectra confirmed the characteristic of metal salen complexes obtained. The central metal atoms in the salen complexes have great influence on the copolymerization of carbon dioxide with propylene oxide. The result shows that chromium metal is more effective to synthesize PPC copolymer. The structure of the resulting PPC was characterized by IR 1H NMR and GPC. 86.3% carbonate content of the PPC was achieved with chromium salen complexes.

Direct Synthesis of Diphenyl Carbonate from Phenol and Carbon Dioxide Over Ti-Salen-Based Catalysts

2015 ◽  
Vol 15 (10) ◽  
pp. 8353-8358 ◽  
Author(s):  
Ki Hyuk Kang ◽  
Jin Oh Jun ◽  
Seung Ju Han ◽  
Kihyeok Kwon ◽  
O-Sung Kwon ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Direct Synthesis ◽  
Metal Species ◽  
Acid Property ◽  
Central Metal Atom ◽  
Diphenyl Carbonate ◽  
Central Metal ◽  
Salen Complexes ◽  
Enhanced Solubility ◽  
Salen Ligand

Various metal-salen catalysts were prepared for use in the direct synthesis of diphenyl carbonate (DPC) from phenol and carbon dioxide. We found that metal-salen complexes containing titanium as central metal species retained suitable Lewis acid property for the reaction. It was revealed that the catalytic activity of Ti-salen complexes could be controlled by introducing appropriate substituents into salen ligand. Insertion of phosphonium salts into para-position of aromatic aldehyde of salen ligand enhanced solubility of the catalyst in the methanol-phenol solution, and tert-butyl substituent in the salen ligand induced selective formation of DPC due to steric effect. In addition, introduction of various bridging groups into salen ligand caused change in electronic property of central metal atom. Among the catalysts tested, Ti-(t-butyl)salphen(PPh3)Cl showed the best catalytic performance at 100 °C and 60 bar. The catalytic system utilizing Ti-(t-butyl)salphen(PPh3)Cl catalyst was then optimized by conducting the reaction at various reaction temperatures and pressures.

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