A sustainable protocol for the facile synthesis of zinc-glutamate MOF: an efficient catalyst for room temperature CO₂fixation reactions under wet conditions

Abstract

A water stable zinc-MOF (ZnGlu) catalyst was facilely prepared from the proteinogenic amino acid, l-glutamic acid at room temperature in aqueous medium. CO2 fixations were promoted by the ZnGlu catalyst's inherently coordinated water and externally added water in yielding cyclic carbonate and cyclic urethane at room temperature. This eliminates the need for catalyst activation, making ZnGlu a ready-to-use catalyst. The enhanced CO2 cycloaddition with added water hints at the application of ZnGlu in wet flue gas conversions. This is the first reported attempt for the use of an MOF in the cycloaddition of aziridine and CO2.

Imidazolium‐Salt‐Functionalized Covalent Organic Frameworks for Highly Efficient Catalysis of CO2 Conversion

“…In these functionalized COFs, the turnover number (TON) of COF-HNU3 was as high as 495 000 (Table 1, entry 1), which is probably ar esulto fi ts high surfacea rea. [47,48] The as-prepared COF-HNU3 and COF-HNU4 have al arge amount of imidazolium cations and Br À anions,w hich can form hydrogen bonds with the epoxide, thus promoting the reaction of epoxides with CO 2 . Nevertheless,C OF-HNU2w ithoutc atalytic sites showedavery low catalytic activity under the same reaction conditions (entry 7).…”

Hollow Zn−Co Based Zeolitic Imidazole Framework as a Robust Heterogeneous Catalyst for Enhanced CO2 Chemical Fixation

“…Moreover, it was observed that the alkyl chain of the quaternary ammonium salts affected the carbonate yield significantly (Entry 2–5). The reactivity decreased following the size of the cations, that is, n Bu 4 N + > n ‐Pr 4 N + >Et 4 N + >Me 4 N + , Table suggesting the reduced interaction of Br − and quaternary ammonium ions favored the activity of this reaction, and thus n Bu 4 NBr with the lowest interaction exhibited the best performance …”

“…The reactivity decreased following the size of the cations, that is, nBu 4 N + > n-Pr 4 N + > Et 4 N + > Me 4 N + ,T able 1s uggesting the reduced interaction of Br À and quaternary ammonium ions favoredt he activity of this reaction,a nd thus nBu 4 NBr with the lowest interaction exhibited the best performance. [67] Binary catalytic systems for the reactions of epoxidesw ith CO 2 coupling usually combine aL ewis acid to make the ringopeningp rocedure energetically and an anionic or basic moiety to bind and activate the polar carbon-oxygen bonds of CO 2 molecule for subsequent insertion. On the basis of these considerations and ther esultso fM OF-catalyzed cycloaddition of CO 2 in this study and literature, [55,56,68] ap ossible reaction path for H-ZnCo-ZIF-catalyzedc ycloadditiono fC O 2 with epoxides is proposed in Scheme 1.…”

Bifunctional Boron Phosphate as an Efficient Catalyst for Epoxide Activation to Synthesize Cyclic Carbonates with CO2

“…In this context, 100 %a tom economical cycloaddition of CO 2 with epoxidesi so ne of the most promising and studied reactions [7][8][9] because the generated five-membered cyclic carbonates can be used as polar solvents, important chemical intermediates, and electrolytes in lithiumb atteries. For the cycloadditiono fC O 2 with epoxides, many homogeneous and heterogeneous catalyst systems have been developed, including alkali metal salts, [10] ionic liquids, [11][12][13] quaternary ammonium and phosphoniums alts, [14][15][16] metal oxides, [17] transition-metalc omplexes, [18][19][20][21][22] functional polymers, [23][24][25][26] and metal-organic frameworks (MOF), [27][28][29][30][31] etc. We have also synthesized Gd-based MOF materials for activating epoxides in the cycloaddition with CO 2 .…”