Crown ether as organocatalyst for reductive upgrading of CO2 to N-containing benzoheterocyclics and N-formamides

Tuneable reduction of CO2 – organocatalyzed selective formylation and methylation of amines

“…However, due to the mismatched catalysis, the cyclization reaction normally requires two steps or harsher conditions than the N-formylation reaction. 13,31,32,39,40 In the previous reports, the N-formylation and N-methylation reactions are assumed to proceed by a general base-catalysed reaction mechanism, in which hydrosilanes are activated by the basic catalyst or the carbamate salt formed. 13 Most recently, the Song group reported the N-methylation and N-formylation reaction between CO 2 and secondary amines in the presence of phenylsilane catalyzed by an ammonium carboxylate ionic liquid.…”

“…One of them is employing cost-efficient reductants. 30 Phenylsilanes have been widely used in the fixation of CO 2 into amines, 26,28,29,31,32 but their use presents some disadvantages since they are expensive, and the byproducts formed are difficult to remove. Polymethylhydrosiloxane (PMHS) is an abundant, low-cost, non-toxic, and highly moisture-stable chemical waste product generated by the silicone industry.…”

Facile Synthesis of Alkaline Ternary Deep Eutectic Solvents: Application for Effective and Reversible SO2 Uptake

“…However, the chemical shifts of H atoms from the −CH 2 – structure in DETA move down field after SO 2 absorption (the blue area). This might be attributed to the electron-withdrawing induction effect from the interaction between Lewis acidic SO 2 and Lewis alkaline DETA . Meanwhile, the chemical shifts of H atoms in ChCl (the green area) and EG (the yellow area) move slightly up field after absorption of SO 2 .…”

“…This might be attributed to the electron-withdrawing induction effect from the interaction between Lewis acidic SO 2 and Lewis alkaline DETA. 39 Meanwhile, the chemical shifts of H atoms in ChCl (the green area) and EG (the yellow area) move slightly up field after absorption of SO 2 . This would be ascribed to the destroyed hydrogen-bonding interaction around ChCl, DETA, and EG, after the introduction of SO 2 , 40 while the 13 C NMR analyses for fresh and SO 2 -saturated ChCl/DETA/EG (1:1:2) show no significant difference (Figure S3 of the Supporting Information), illustrating the scarcely unhappened interaction between SO 2 and C atoms in DES.…”