Highly Efficient Conversion of Propargylic Amines and CO₂ Catalyzed by Noble‐Metal‐Free [Zn₁₁₆] Nanocages

Abstract

The reaction of propargylic amines and CO 2 can provideh igh-value-added chemical products.H owever,m ost of catalysts in such reactions employn oble metals to obtain high yield, and it is important to seek eco-friendly noble-metalfree MOFs catalysts.H ere,agiant and lantern-like [Zn 116 ] nanocage in zinc-tetrazole 3D framework [Zn 22 (Trz) 8 (OH) 12 -(H 2 O) 9 ·8 H 2 O] n Trz = (C 4 N 12 O) 4À (1)w as obtained and structurally characterized.I tc onsists of six [Zn 14 O 21 ]c lusters and eight [Zn 4 O 4 ]c lusters.T oo ur knowledge,t his is the highestnuclearity nanocages constructed by Zn-clusters as building blocks to date.Importantly,catalytic investigations reveal that 1 can efficiently catalyze the cycloaddition of propargylic amines with CO 2 ,e xclusively affording various 2-oxazolidinones under mild conditions.I ti st he first eco-friendly noblemetal-free MOFs catalyst for the cyclization of propargylic amines with CO 2 .DFT calculations uncover that Zn II ions can efficiently activate both C Cbonds of propargylic amines and CO 2 by coordination interaction. NMR and FTIR spectroscopy further prove that Zn-clusters play an important role in activating CCbonds of propargylic amines.Furthermore,the electronic properties of related reactants,i ntermediates and products can help to understand the basic reaction mechanism and crucial role of catalyst 1. Scheme 2. a) Reaction pathway for cycloaddition of CO 2 with propargylic amines obtained utilizing climbingimage nudged elastic band method;b)The reaction energies (E react )o fsubstrate molecules and CO 2 and the corresponding yield of oxazolidinones. Angewandte Chemie Forschungsartikel 8669

Ambient Chemical Fixation of CO2 Using a Robust Ag27 Cluster‐Based Two‐Dimensional Metal–Organic Framework

“…However, catalytic sites in the micro‐structure remain unchanged and do not fall out from the framework, thus concluding the post‐catalysis structure is stable. The similar PXRD change has been already observed for many other recyclable MOF‐based catalysts [15, 24] . For comparison, the catalytic activity of a serious of inorganic silver salts for this model reaction has also been studied.…”

Recent Advances in the Chemistry of Metal Carbamates

“…The formation of carbamato complexes is considered a key step in metal-mediated reactions such as the CO 2 /aziridine coupling [306][307][308] and the CO 2 cycloaddition to propargyl amines [113,[309][310][311][312] or aminoalcohols [306]. The production of oxazolidinones (cyclic carbamates) via CO 2 /aziridine coupling is one of the most widely investigated carbon dioxide fixation processes, and many species have been evaluated as catalytic precursors, such as Al(III) [313], Cr(III) [314] and Co(III) [315] salen complexes, and Cu(II) [316] and Zn(II) [317] porphyrin complexes.…”

Ambient Chemical Fixation of CO2 Using a Robust Ag27 Cluster‐Based Two‐Dimensional Metal–Organic Framework

“…However, catalytic sites in the micro-structure remain unchanged and do not fall out from the framework, thus concluding the postcatalysis structure is stable.T he similar PXRD change has been already observed for many other recyclable MOF-based catalysts. [15,24] Forc omparison, the catalytic activity of as erious of inorganic silver salts for this model reaction has also been studied. Control experiments indicated that the homogenous AgStBu and CF 3 COOAg provided low yields under similar conditions (Table 1, entries 8and 9).…”