Carboxylative Cyclization Of Propargylic Alcohols Research Articles

Azaphosphatrane/Ag2O catalyzed the carboxylative cyclization of propargylic alcohols and CO2

The utilization of carbon dioxide (CO2) to synthesize various chemicals is of great importance. Herein, various azaphosphatranes and silver salts were applied to catalyze the carboxylative cyclization of CO2 and propargylic alcohols to prepare α-methylene cyclic carbonates. The influences of catalyst structures, solvents and reaction parameters on catalytic performance were systematically studied. The combination of tris(4-methoxybenzyl) azaphosphatranes (PMB-AZAP) and Ag2O with molar ratio of 0.5:1 gave α-methylene cyclic carbonate in the yield of >99 % at room temperature. Meanwhile, other azaphosphatranes (i-Bu-AZAP, Me-AZAP) gave the product in slightly lower yields. The mechanism exploration revealed that PMB-AZAP and Ag2O formed a silver complex PMB-AZAP-Ag during the reaction, which could synergistically catalyze carboxylative cyclization reaction with PMB-AZAP, resulting in a high product yield. In contrast, AgCl or AgNO3 couldn't react with PMB-AZAP to form silver complexes, and the corresponding catalytic system had no activity. The difference of the catalytic performance indicated that PMB-AZAP-Ag was a key active species for the carboxylative cyclization reaction. The in situ NMR studies concretely demonstrated that PMB-AZAP could activate propargylic alcohols through hydrogen bonding. Furthermore, the catalytic system had good substrate generality. The PMB-AZAP/Ag2O was also applied for the one-pot reaction of propargylic alcohol, CO2 and CH3OH, affording the β-carbonyl carbonate with yield of 80 % at CH3OH/propargylic alcohols ratio of 20:1.

In Situ Anchoring of Small-Sized Silver Nanoparticles on Porphyrinic Triazine-Based Frameworks for the Conversion of CO2 into α-Alkylidene Cyclic Carbonates with Outstanding Catalytic Activities under Ambient Conditions.

The preparation of catalytic hybrid materials by introducing highly dispersed metallic nanoparticles into porous organic polymers (POPs) may be an ideal and promising strategy for integrated CO2 capture and conversion. In terms of the carboxylative cyclization of propargyl alcohols with CO2, the anchoring of silver nanoparticles (AgNPs) on functional POPs to fabricate efficient heterogeneous catalysts is considered to be quite intriguing but remains challenging. In the contribution, well-dispersed AgNPs were successfully anchored onto the porphyrinic triazine-based frameworks by a simple "liquid impregnation and in situ reduction" strategy. The presence of N-rich dual active sites, porphyrin and triazine, which acted as the electron donor and acceptor, respectively, offered a huge opportunity for the nucleation and growth of metal nanoparticles. Significantly, the as-prepared catalyst Ag/TPP-CTF shows excellent catalytic activity (up to 99%) toward the carboxylative cyclization of propargyl alcohols with CO2 at room temperature, achieving record-breaking activities (TOF up to 615 h-1 at 1 bar and 3077 h-1 at 10 bar). Moreover, the catalyst can be easily recovered and reused at least 10 times with retention of high catalytic activity. The possible mechanism involves small-sized AgNP-mediated alkyne activation, which may promote highly efficient and green conversion of CO2. This work paves the way for immobilizing metal nanoparticles onto functional POPs by surface structure changes for enhanced CO2 catalysis.

Carboxylative cyclization of propargyl alcohols with carbon dioxide for the synthesis of α-alkylidene cyclic carbonates in presence of Co(III) schiff base complex catalyst

A cobalt(III) complex, [Co(L)3](DMF) (1) of Schiff base ligand HL, 2-((E)-(benzylimino)methyl)-4-bromophenol is prepared and single crystal X-ray structural analysis have also been performed. The structures of complex 1 showed hexa-coordinated mononuclear systems that adopt octahedral geometry. The complex has also exhibited the supramolecular networks through non-covalent interactions like H-bonding, C–Hπ stacking. Moreover, the complex 1 is very effective in the catalytic fixation of carbon dioxide in propergyl alcohols to produce α-alkylidene cyclic carbonates. The catalytic production of α-alkylidene cyclic carbonates have been carried out through carboxylative cyclization of propargyl alcohols using CO2 balloon of 1 atm pressure at 80 °C. Solvent free condition (green synthesis) made this catalytic protocol eco-friendly towards the environment. Utilizing various substrates of propargyl alcohols moderate to high percentage yield (62–95%) of respective α-alkylidene cyclic carbonates product have been isolated over this catalytic reaction. Besides, the theoretical calculations (DFT) was performed for the prediction of probable mechanism of the catalytic reaction.

Ag Nanoparticles Anchored on Nanotubular Porous Porphyrin Networks for Carboxylative Cyclization of Propargyl Alcohols with CO2

AbstractA nanotubular porous porphyrin‐based network (NT‐PPN) was prepared through Friedel–Crafts alkylation polyreaction of meso‐tetraphenylporphyrin iron chloride and subsequent demetalization reaction with concentrated hydrochloric acid. As a superior support, NT‐PPN was decorated with Ag nanoparticles to generate the desired catalyst (Ag@NT‐PPN). Ag@NT‐PPN had a high BET surface area with plentiful hierarchical porosity, considerable CO2 adsorption uptake, as well as high CO2/N2 adsorption selectivity. In the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU), Ag@NT‐PPN exhibited excellent catalytic performance for the solvent‐free synthesis of α‐alkylidene cyclic carbonates from propargyl alcohols and CO2 at 30 °C. Ag@NT‐PPN also displayed robust constancy, excellent recyclability, and acceptable substrate expansibility for this reaction. Moreover, low concentration of CO2 derived from mixed gas (15% CO2+85% N2 in volume) was positively amenable to this catalytic protocol. This work might offer an opportunity to design metal NPs‐based heterogeneous catalysts and provide a promising candidate for application in the transformation of CO2 into valuable cyclic carbonates.

Pyridinylidenaminophosphines as Versatile Organocatalysts for CO2 Transformations into Value‐Added Chemicals

AbstractThe carboxylative cyclization of propargylic alcohols with CO2 was developed employing pyridinylidenaminophosphines (PYA‐Ps) as organocatalyts for the first time. Moderate to good yields of α‐methylene cyclic carbonates were obtained with excellent chemo‐ and stereo‐selectivity. Density functional theory (DFT) calculations reveal that the catalytic reaction tends to proceed via the PYA‐Ps‐mediated basic ionic pair mechanism, and the intramolecular cyclization should be the rate determining step. Furthermore, the catalytic diversity of PYA‐Ps was investigated for the chemical transformations of CO2 to functionalized cyclic carbonates and N‐formylated amines.

Anchoring Ag(I) into Nitro-Functionalized Metal–Organic Frameworks: Effectively Catalyzing Cycloaddition of CO2 with Propargylic Alcohols under Mild Conditions

Carboxylative cyclization of propargylic alcohols with CO2 is significant in synthetic chemistry, but harsh conditions are often needed according to reported results. Herein, a new stable nitro-functionalized metal-organic framework (MOF) of {[Co3(L)2(bpy)4(H2O)2]·DMF·H2O·bpy}n (1) was fabricated through the solvothermal reaction, which exhibited excellent stability in acid and basic solutions. Owing to the porous structure, unsaturated metal sites, and uncoordinated 4,4'-bpy ligands, 1 can serve as an excellent platform for catalytic applications. Hence, Ag(I) ions were incorporated in 1 through a postsynthetic method, and the as-synthesized Ag-1 catalyst with low metal loading (0.64 mol %) displayed excellent catalytic performance in the chemical fixation of CO2 with alkynols under room temperature and atmospheric pressure. The results of 1H NMR analyses further confirmed that Ag-1 can efficiently activate hydroxyl groups and promote the reaction. Moreover, the turnover frequency (TOF) of the Ag-1 catalyst can reach 262 h-1 in a short period of time, which is a high TOF value among the state-of-the-art MOF-based catalysts for catalyzing cycloaddition of CO2 with propargylic alcohols.

Carboxylative Cyclization of Propargylic Alcohols on a Vanadium–Copper Metal–Organic Framework

Key words copper catalysis - vanadium catalysis - metal­organic framework - propargylic alcohols - carboxylative cyclization - carbon dioxide

Reduced Graphene Oxide Supported Ag Nanoparticles: An Efficient Catalyst for CO2 Conversion at Ambient Conditions

AbstractA highly efficient carboxylative cyclization of propargylic alcohols with CO2 under atmospheric pressure catalyzed by silver (0) nanoparticles decorated reduced graphene oxide (Ag‐rGO) is reported. Ag‐rGO was fully characterized by scanning electron microscope spectra (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR) spectra, Raman spectra and X‐ray photoelectron spectroscopy (XPS). Notably, Ag‐rGO can be also applied to the construction of other value‐added chemicals (β‐oxopropylcarbamates and 2‐oxazolidinones) from CO2 at ambient conditions. In addition, Ag‐rGO is stable and reusable, which shows the potential for the practical application for CO2 capture and utilization (CCU).

Silver-Catalyzed Carboxylative Cyclization of Propargylic Alcohols

Key words silver catalysis - carboxylative cyclization - propagylic alcohols - dioxolanones - catalyst support - rose bengal

Zinc (II) incorporated porous organic polymeric material (POPs): A mild and efficient catalyst for synthesis of dicoumarols and carboxylative cyclization of propargyl alcohols and CO2 in ambient conditions

Zinc (II) incorporated porous organic polymer catalyst, Zn@BBAPA has been designed, synthesized and characterized thoroughly by XRD, EDX, SEM, HR-TEM, FTIR spectra, UV–vis spectra, TGA and N2 absorption desorption isotherm. An eco-friendly porous Zn@BBAPA catalyst exhibits highly efficient catalytic performance for the production of α-alkylidene cyclic carbonates by using propargylic alcohols viaCO2 fixation.In addition the catalyst shows outstanding efficiency for the synthesis of various dicoumarol derivatives in green solvent medium (water)from 4-hydroxycoumarin and aromatic aldehydes. Presence of super hydrophobic nature and electron-donation characterof NH2 groups of BBA framework with high surface area is main aspect to be responsible for elevated catalytic performance as well as improvement in catalyst stability and enabling a good recyclability.

Enantioselective carboxylative cyclization of propargylic alcohol with carbon dioxide under mild conditions

An enantioselective carboxylative cyclization of propargylic alcohols and CO2 was realized under mild conditions, based on a kinetic resolution strategy, which enabled the synthesis of chiral cyclic carbonates and propargylic alcohols with promising yield and enantioselectivity simultaneously.

Transformation of CO2 into α-Alkylidene Cyclic Carbonates at Room Temperature Cocatalyzed by CuI and Ionic Liquid with Biomass-Derived Levulinate Anion

Utilization of carbon dioxide (CO2) as a renewable C1 building block is of great importance. Herein, a series of ionic liquids (ILs) with biomass-derived anions or/and cations were synthesized, and using these prepared ILs as catalytic solvents, CuI could catalyze carboxylative cyclization of propargylic alcohols with CO2 at room temperature (25 °C). Especially, the IL [Bu4P][Levulinate] with cellulose-derived levulinate anion combined with CuI showed the best performance, affording various corresponding α-alkylidene cyclic carbonates in good yields (>90%). In the reaction, CuI and [Bu4P][Levulinate] played synergistic role to activate the C≡C and hydroxyl groups in propargylic alcohols, respectively, leading to the excellent performance of CuI/[Bu4P][Levuliniate]. Additionally, the CuI/[Bu4P][Levuliniate] catalytic system could be reused for five times without noticeable decrease in activity and selectivity.

Copper(i) iodide cluster-based lanthanide organic frameworks: synthesis and application as efficient catalysts for carboxylative cyclization of propargyl alcohols with CO2 under mild conditions.

Two metal-organic frameworks (MOFs), namely, [Dy2Cu4I4(NA)6(DMF)2]n (1) and [Gd2Cu2I2(IN)6(DMF)4]·5DMF (2) (HNA = nicotinic acid, HIN = isonicotinic acid), constructed based on lanthanide ions and copper iodide clusters ([Cu4I4] and [Cu2I2]) were successfully synthesized and characterized. Compound 1 has a three-dimensional framework and compound 2 displays a two-dimensional plane with sql topology, respectively. Both of them exhibit high thermostability and solvent stabilities. Additionally, catalytic explorations reveal that 1 displays higher catalytic activity than 2 for the carboxylic cyclization of propargyl alcohols. More importantly, 1 also exhibits excellent catalytic performance in the carboxylation reactions of CO2 and terminal propargylic alcohols with various substituents. To the best of our knowledge, this is the first example of non-noble metal based MOF catalysts for the carboxylative cyclization of propargyl alcohols with CO2 under atmospheric pressure and at room temperature, which provides a highly promising approach for MOFs in the catalytic conversion of CO2 to valuable chemicals.

A rose bengal-functionalized porous organic polymer for carboxylative cyclization of propargyl alcohols with CO2.

A Rose bengal-functionalized porous organic polymer (RB-POP) was prepared with a specific surface area of up to 562 m2 g-1. In the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, RB-POP supported Ag(0) nanoparticles exhibited excellent performance for catalyzing cyclization of propargyl alcohols with CO2 at 30 °C, achieving a TOF of 5000 h-1, the highest value among the reported ones.

Remarkable synergistic effect between copper(I) and ionic liquids for promoting chemical fixation of CO2

Recently, efficient chemical conversion of CO2 into high value chemicals at room temperature and atmospheric pressure without using noble metal catalysts remains a great challenge. In this work, we find that the carboxylative cyclization of propargylic alcohols with CO2 can proceed at 60°C and ambient pressure by using a combination of CuI and an ionic liquid (IL) 1,8-diazabicyclo-[5.4.0]-7-undecenium trifluoroethanol ([DBUH][TFE]) as catalyst. By simple extraction after the reactions, a series of desired products have been obtained in good to excellent yields with this highly efficient catalyst system. Spectroscopic investigations and DFT calculations demonstrate that such a high efficiency originates from remarkable synergistic catalysis between Cu(I) and the IL on substrates. In addition, it is worth noting that this catalyst system also works well for the carboxylative cyclization of propargylic amines even at ambient temperature and pressure, with the highest turnover number among the reported base metals catalytic systems.

One‐pot carboxylative cyclization of propargylic alcohols and CO2 catalysed by N‐heterocyclic carbene/Ag systems

A series of N‐heterocyclic carbene (NHC)/Ag systems were developed for the carboxylative assembly of propargylic alcohols and carbon dioxide (CO2). With the catalysis of these catalytic systems, a variety of target α‐alkylidene cyclic carbonates could be obtained smoothly under atmospheric CO2 pressure in straightforward one‐pot processes. Particularly, these reactions could be performed without any stoichiometric addition of bases or additives. Further mechanistic investigation reveals that the excellent activities are attributed to the effective activations of CO2 accomplished by the NHCs via the formation of the NHC‐CO2 adducts.

ChemInform Abstract: Robust Silver(I) Catalyst for the Carboxylative Cyclization of Propargylic Alcohols with Carbon Dioxide under Ambient Conditions.

Inspired by the bulkier bis(triphenylphosphine)–silver cation-induced mechanism of propargylic alcohols and carbon dioxide through the alkyl carbonate intermediate, a robust dual-component catalytic system consisting of silver acetate and tetraheptylammonium bromide was rationally developed for the synthesis of α-methylene cyclic carbonates under ambient conditions without employing any additional organic base and ligand. This is one of the most effective catalysts reported to date for this conversion, with a very high turnover number of up to 6024, probably due to the synergistic effect of Lewis basic and Lewis acidic species for the activation of both propargylic alcohol and carbon dioxide by the formation of the alkyl carbonate with a bulkier counterion. Notably, this catalyst also worked well for the carboxylative cyclization of propargylic amines with carbon dioxide with the highest turnover number of 544.

ChemInform Abstract: Green Catalytic Process for Cyclic Carbonate Synthesis from Carbon Dioxide under Mild Conditions

AbstractReview: [108 refs.

Silver(I)-Catalyzed Three-Component Reaction of Propargylic Alcohols, Carbon Dioxide and Monohydric Alcohols: Thermodynamically Feasible Access to β-Oxopropyl Carbonates.

A silver(I)-catalyzed three-component reaction of propargylic alcohols, CO2 , and monohydric alcohols was successfully developed for the synthesis of β-oxopropyl carbonates. As such, a series of β-oxopropyl carbonates were exclusively produced in excellent yields (up to 98 %), even under atmospheric pressure of CO2 . The silver catalyst works efficiently for both the carboxylative cyclization of propargylic alcohols with CO2 and subsequent transesterification of α-alkylidene cyclic carbonates with monohydric alcohols; thus this tandem process performs smoothly under mild conditions. This work provides a versatile and thermodynamically favorable approach to dissymmetric dialkyl carbonates.

ChemInform Abstract: Zinc(II)‐Catalyzed Reactions of Carbon Dioxide and Propargylic Alcohols to Carbonates at Room Temperature.

AbstractAlkylidiene cyclic carbonates are prepared by carboxylative cyclization of propargylic alcohols with CO2 using ZnI2/NEt3 as synergistic catalytic system.