The role of zinc oxide in carbonylation of ethylene glycol to ethylene carbonate with urea: A precursor for homogeneous catalyst

Lewis Acid–Base Synergistic Catalysis for Polyethylene Terephthalate Degradation by 1,3-Dimethylurea/Zn(OAc)2 Deep Eutectic Solvent

“…It was reported that Zn­(OAc) 2 can react with polyol to form ZnO . Moreover, ZnO was an effective catalyst in the urea glycolysis process to synthesis ethylene carbonate . However, 3-methyl-oxazolidin-2-one was detected in the mixture of DES and EG after heating but not detected in the mixture of DES, EG, and PET (Figure S11).…”

“…34 Moreover, ZnO was an effective catalyst in the urea glycolysis process to synthesis ethylene carbonate. 35 However, 3-methyl-oxazolidin-2-one was detected in the mixture of DES and EG after heating but not detected in the mixture of DES, EG, and PET (Figure S11). The reason for the difference was speculated to be that the PET glycolysis reaction and the 1,3-DMU glycolysis reaction are mutually competing, and the hydrolysis of Zn(OAc) 2 is also inhibited in the presence of PET.…”

Incorporation of CO2 into carbonates through carboxylation/hydration reaction

“…Very recently, the role of ZnO in the carbonylation of EG with urea was studied, and the catalytic procedures included three stages: ZnO dissolution, homogeneous catalysis, and precipitate formation (Scheme ). The precipitate composition after the reaction was further studied and the results showed that the precipitate was a mixture of Zn(OH) 2 , ZnCO 3 and Zn(NCO) 2 :…”

“…138 Very recently, the role of ZnO in the carbonylation of EG with urea was studied, and the catalytic procedures included three stages: ZnO dissolution, homogeneous catalysis, and precipitate formation (Scheme 26). The precipitate composition after the reaction was further studied and the results showed that the precipitate was a mixture of Zn(OH) 2 , ZnCO 3 and Zn(NCO) 2 : 139 La(NO 3 ) 3 also acted as a candidate in urea alcoholysis in a batch reactor, and the reaction temperature was proved to have a significant influence on PC yield. By removing the ammonia byproduct under reduced pressure, the EC yield was raised to 93%.…”

Straight Access to Indoles from Anilines and Ethylene Glycol by Heterogeneous Acceptorless Dehydrogenative Condensation

“…However, when ethylene glycol was used, a tautomeric equilibrium of this imine in combination with Pt/Al 2 O 3 limited rehydrogenation capacity, yielding a different compound for indole formation. Madsen, Williams, and Bruneau have reported on a similar tautomeric feature with amino alcohols under BH reactions in homogeneous phase. ,, The use of ZnO nanoparticles as a catalyst has recently been reported. , In our case, the small particle size and the solubility of this oxide may be responsible of an easier coparticipation between ZnO and Pt/Al 2 O 3 in the first step of the catalytic cycle. The formation of 3 , 4 , or 5 as side products clearly indicates that the C–N bond formation is the first step as no side products derived from an initial cyclization (formation of C–C bond and then formation of the C–N bond) have ever been observed.…”