1589596-00-8Relevant academic research and scientific papers
Alkoxide-functionalized imidazolium betaines for CO2 activation and catalytic transformation
Wang, Yan-Bo,Sun, Dong-Sheng,Zhou, Hui,Zhang, Wen-Zhen,Lu, Xiao-Bing
, p. 2266 - 2272 (2014/04/17)
Alkoxide-functionalized imidazolium betaines (AFIBs), including an alkoxide anion and an imidazolium cation, were synthesized by treating potassium tert-butoxide with 1-(2-hydroxyethyl)-2,3-disubstituted imidazolium bromide. The novel betaines were able to quickly capture CO2, affording carboxylate zwitterions (AFIB-CO2 adducts). In the presence of adventitious water, the transformation of the AFIB-CO2 adducts into the corresponding bicarbonate salts was observed by 1H and 13C NMR spectroscopy. The structures of the AFIB bicarbonate salts were solved using single crystal X-ray crystallography. Furthermore, the dithiocarboxylate zwitterions (AFIB-CS2 adducts), which are more stable to moisture in comparison with their CO2 adducts, were prepared by reacting CS2 with the corresponding betaines. X-Ray single crystal analysis revealed the bent geometry of the binding CS2 in the dithiocarboxylate zwitterions with a S-C-S angle of 126.6-126.9°, which indirectly confirms the structures of the AFIB-CO2 adducts in hand. These AFIB-CO2 adducts were found to function as organocatalysts for the coupling reaction of propargylic alcohols with CO 2 for selectively producing valuable cyclic carbonates under mild and solvent-free reaction conditions. the Partner Organisations 2014.
