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Search for "eutectic solvent" in Full Text gives 8 result(s) in Beilstein Journal of Organic Chemistry.
Recent advances in synthetic approaches for bioactive cinnamic acid derivatives
- Betty A. Kustiana,
- Galuh Widiyarti and
- Teni Ernawati
Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85
- cinnamic acid (7) in a deep eutectic solvent of choline chloride/urea (ChCl/urea) to give amides 12 and 13 in moderate yields via triacylated triazine 14 as the active ester (Scheme 5A) [36]. The TCT reagent and ChCl/urea solvent are known for their non-toxicity and low cost, promoting their wide
Graphical Abstract
Figure 1: Biologically active cinnamic acid derivatives.
Scheme 1: General synthetic strategies for cinnamic acid derivatizations.
Scheme 2: Cinnamic acid coupling via isobutyl anhydride formation.
Scheme 3: Amidation reaction via O/N-pivaloyl activation.
Scheme 4: Cinnamic acid amidation using TCCA/PPh3 reagent.
Scheme 5: Cinnamic acid amidation using triazine-based reagents.
Scheme 6: Cinnamic acid amidation using continuous flow mechanochemistry.
Scheme 7: Cinnamic acid amidation using COMU as coupling reagent.
Scheme 8: Cinnamic acid amidation using allenone coupling reagent.
Scheme 9: Cinnamic acid amidation using 4-acetamidophenyl triflimide as reagent.
Scheme 10: Cinnamic acid amidation using methyltrimethoxysilane (MTM).
Scheme 11: Cinnamic acid amidation utilizing amine–borane reagent.
Scheme 12: Cinnamic acid amidation using TCCA/PPh3 reagent.
Scheme 13: Cinnamic acid amidation using PPh3/I2 reagent.
Scheme 14: Cinnamic acid amidation using PCl3 reagent.
Scheme 15: Cinnamic acid amidation utilizing pentafluoropyridine (PFP) as reagent.
Scheme 16: Cinnamic acid amidation using hypervalent iodine(III).
Scheme 17: Mechanochemical amidation using 1,1,2,2-tetrafluoroethyl-N,N-dimethylamine (TFEDMA) reagent.
Scheme 18: Methyl ester preparation using tris(2,4,6-trimethoxyphenyl)phosphine (TMPP).
Scheme 19: N-Trifluoromethyl amide preparation using isothiocyanate and AgF.
Scheme 20: POCl3-mediated amide coupling of carboxylic acid and DMF.
Scheme 21: O-Alkylation of cinnamic acid using alkylating agents.
Scheme 22: Glycoside preparation via Mitsunobu reaction.
Scheme 23: O/N-Acylation via rearrangement reactions.
Scheme 24: Amidation reactions using sulfur-based alkylating agents.
Scheme 25: Amidation reaction catalyzed by Pd0 via C–N cleavage.
Scheme 26: Amidation reaction catalyzed by CuCl/PPh3.
Scheme 27: Cu(II) triflate-catalyzed N-difluoroethylimide synthesis.
Scheme 28: Cu/Selectfluor-catalyzed transamidation reaction.
Scheme 29: CuO–CaCO3-catalyzed amidation reaction.
Scheme 30: Ni-catalyzed reductive amidation.
Scheme 31: Lewis acidic transition-metal-catalyzed O/N-acylations.
Scheme 32: Visible-light-promoted amidation of cinnamic acid.
Scheme 33: Sunlight/LED-promoted amidation of cinnamic acid.
Scheme 34: Organophotocatalyst-promoted N–O cleavage of Weinreb amides to synthesize primary amides.
Scheme 35: Cinnamamide synthesis through [Ir] photocatalyst-promoted C–N-bond cleavage of tertiary amines.
Scheme 36: Blue LED-promoted FeCl3-catalyzed reductive transamidation.
Scheme 37: FPyr/TCT-catalyzed amidation of cinnamic acid derivative 121.
Scheme 38: Cs2CO3/DMAP-mediated esterification.
Scheme 39: HBTM organocatalyzed atroposelective N-acylation.
Scheme 40: BH3-catalyzed N-acylation reactions.
Scheme 41: Borane-catalyzed N-acylation reactions.
Scheme 42: Catalytic N-acylation reactions via H/F bonding activation.
Scheme 43: Brønsted base-catalyzed synthesis of cinnamic acid esters.
Scheme 44: DABCO/Fe3O4-catalyzed N-methyl amidation of cinnamic acid 122.
Scheme 45: Catalytic oxidation reactions of acylating agents.
Scheme 46: Preparation of cinnamamide-substituted benzocyclooctene using I(I)/I(III) catalysis.
Scheme 47: Pd-colloids-catalyzed oxidative esterification of cinnamyl alcohol.
Scheme 48: Graphene-supported Pd/Au alloy-catalyzed oxidative esterification via hemiacetal intermediate.
Scheme 49: Au-supported on A) carbon nanotubes (CNT) and B) on porous boron nitride (pBN) as catalyst for the ...
Scheme 50: Cr-based catalyzed oxidative esterification of cinnamyl alcohols with H2O2 as the oxidant.
Scheme 51: Co-based catalysts used for oxidative esterification of cinnamyl alcohol.
Scheme 52: Iron (A) and copper (B)-catalyzed oxidative esterification of cinnamaldehyde.
Scheme 53: NiHPMA-catalyzed oxidative esterification of cinnamaldehyde.
Scheme 54: Synthesis of cinammic acid esters through NHC-catalyzed oxidative esterification via intermolecular...
Scheme 55: Redox-active NHC-catalyzed esterification via intramolecular oxidation.
Scheme 56: Electrochemical conversion of cinnamaldehyde to methyl cinnamate.
Scheme 57: Bu4NI/TBHP-catalyzed synthesis of bisamides from cinnamalaldehyde N-tosylhydrazone.
Scheme 58: Zn/NC-950-catalyzed oxidative esterification of ketone 182.
Scheme 59: Ru-catalyzed oxidative carboxylation of terminal alkenes.
Scheme 60: Direct carboxylation of alkenes using CO2.
Scheme 61: Carboxylation of alkenylboronic acid/ester.
Scheme 62: Carboxylation of gem-difluoroalkenes with CO2.
Scheme 63: Photoredox-catalyzed carboxylation of difluoroalkenes.
Scheme 64: Ru-catalyzed carboxylation of alkenyl halide.
Scheme 65: Carboxylation of alkenyl halides under flow conditions.
Scheme 66: Cinnamic acid ester syntheses through carboxylation of alkenyl sulfides/sulfones.
Scheme 67: Cinnamic acid derivatives synthesis through a Ag-catalyzed decarboxylative cross-coupling proceedin...
Scheme 68: Pd-catalyzed alkyne hydrocarbonylation.
Scheme 69: Fe-catalyzed alkyne hydrocarbonylation.
Scheme 70: Alkyne hydrocarboxylation using CO2.
Scheme 71: Alkyne hydrocarboxylation using HCO2H as CO surrogate.
Scheme 72: Co/AlMe3-catalyzed alkyne hydrocarboxylation using DMF.
Scheme 73: Au-catalyzed oxidation of Au–allenylidenes.
Scheme 74: Pd-catalyzed C–C-bond activation of cyclopropenones to synthesize unsaturated esters and amides.
Scheme 75: Ag-catalyzed C–C-bond activation of diphenylcyclopropenone.
Scheme 76: Cu-catalyzed C–C bond activation of diphenylcyclopropenone.
Scheme 77: PPh3-catalyzed C–C-bond activation of diphenylcyclopropenone.
Scheme 78: Catalyst-free C–C-bond activation of diphenylcyclopropenone.
Scheme 79: Cu-catalyzed dioxolane cleavage.
Scheme 80: Multicomponent coupling reactions.
Scheme 81: Pd-catalyzed partial hydrogenation of electrophilic alkynes.
Scheme 82: Nickel and cobalt as earth-abundant transition metals used as catalysts for the partial hydrogenati...
Scheme 83: Metal-free-catalyzed partial hydrogenation of conjugated alkynes.
Scheme 84: Horner–Wadsworth–Emmons reaction between triethyl 2-fluoro-2-phosphonoacetate and aldehydes with ei...
Scheme 85: Preparation of E/Z-cinnamates using thiouronium ylides.
Scheme 86: Transition-metal-catalyzed ylide reactions.
Scheme 87: Redox-driven ylide reactions.
Scheme 88: Noble transition-metal-catalyzed olefination via carbenoid species.
Scheme 89: TrBF4-catalyzed olefination via carbene species.
Scheme 90: Grubbs catalyst (cat 7)/photocatalyst-mediated metathesis reactions.
Scheme 91: Elemental I2-catalyzed carbonyl-olefin metathesis.
Scheme 92: Cu-photocatalyzed E-to-Z isomerization of cinnamic acid derivatives.
Scheme 93: Ni-catalyzed E-to-Z isomerization.
Scheme 94: Dehydration of β-hydroxy esters via an E1cB mechanism to access (E)-cinnamic acid esters.
Scheme 95: Domino ring-opening reaction induced by a base.
Scheme 96: Dehydroamination of α-aminoester derivatives.
Scheme 97: Accessing methyl cinnamate (44) via metal-free deamination or decarboxylation.
Scheme 98: The core–shell magnetic nanosupport-catalyzed condensation reaction.
Scheme 99: Accessing cinnamic acid derivatives from acetic acid esters/amides through α-olefination.
Scheme 100: Accessing cinnamic acid derivatives via acceptorless α,β-dehydrogenation.
Scheme 101: Cu-catalyzed formal [3 + 2] cycloaddition.
Scheme 102: Pd-catalyzed C–C bond formation via 1,4-Pd-shift.
Scheme 103: NHC-catalyzed Rauhut–Currier reactions.
Scheme 104: Heck-type reaction for Cα arylation.
Scheme 105: Cu-catalyzed trifluoromethylation of cinnamamide.
Scheme 106: Ru-catalyzed alkenylation of arenes using directing groups.
Scheme 107: Earth-abundant transition-metal-catalyzed hydroarylation of α,β-alkynyl ester 374.
Scheme 108: Precious transition-metal-catalyzed β-arylation of cinnamic acid amide/ester.
Scheme 109: Pd-catalyzed β-amination of cinnamamide.
Scheme 110: S8-mediated β-amination of methyl cinnamate (44).
Scheme 111: Pd-catalyzed cross-coupling reaction of alkynyl esters with phenylsilanes.
Scheme 112: Pd-catalyzed β-cyanation of alkynyl amide/ester.
Scheme 113: Au-catalyzed β-amination of alkynyl ester 374.
Scheme 114: Metal-free-catalyzed Cβ-functionalizations of alkynyl esters.
Scheme 115: Heck-type reactions.
Scheme 116: Mizoroki–Heck coupling reactions using unconventional functionalized arenes.
Scheme 117: Functional group-directed Mizoroki–Heck coupling reactions.
Scheme 118: Pd nanoparticles-catalyzed Mizoroki–Heck coupling reactions.
Scheme 119: Catellani-type reactions to access methyl cinnamate with multifunctionalized arene.
Scheme 120: Multicomponent coupling reactions.
Scheme 121: Single atom Pt-catalyzed Heck coupling reaction.
Scheme 122: Earth-abundant transition metal-catalyzed Heck coupling reactions.
Scheme 123: Polymer-coated earth-abundant transition metals-catalyzed Heck coupling reactions.
Scheme 124: Earth-abundant transition-metal-based nanoparticles as catalysts for Heck coupling reactions.
Scheme 125: CN- and Si-based directing groups to access o-selective cinnamic acid derivatives.
Scheme 126: Amide-based directing group to access o-selective cinnamic acid derivatives.
Scheme 127: Carbonyl-based directing group to access o-selective cinnamic acid derivatives.
Scheme 128: Stereoselective preparation of atropisomers via o-selective C(sp2)–H functionalization.
Scheme 129: meta-Selective C(sp2)–H functionalization using directing group-tethered arenes.
Scheme 130: para-Selective C(sp2)–H functionalization using directing group-tethered arenes.
Scheme 131: Non-directed C(sp2)–H functionalization via electrooxidative Fujiwara–Moritani reaction.
Scheme 132: Interconversion of functional groups attached to cinnamic acid.
Scheme 133: meta-Selective C(sp2)–H functionalization of cinnamate ester.
Scheme 134: C(sp2)–F arylation using Grignard reagents.
Scheme 135: Truce–Smiles rearrangement of N-aryl metacrylamides.
Scheme 136: Phosphine-catalyzed cyclization of γ-vinyl allenoate with enamino esters.
Cell-free protein synthesis with technical additives – expanding the parameter space of in vitro gene expression
- Tabea Bartsch,
- Stephan Lütz and
- Katrin Rosenthal
Beilstein J. Org. Chem. 2024, 20, 2242–2253, doi:10.3762/bjoc.20.192
- system increases to 1329 mOsm. Next to choline chloride/urea and choline chloride/glycerol, betaine/ethylene glycol (EG) was tested as it is considered to be an environmentally friendly natural deep eutectic solvent (NADES) [30] and is widely used with proteins [31]. As it does not consist of any ions
Graphical Abstract
Figure 1: CFPS of sfGFP with different technical additives at various concentrations. Experiments with 2% PEG...
Figure 2: CFPS of thscGAS-sfGFP with different technical additives at various concentrations. Experiments wit...
Electrochemical allylations in a deep eutectic solvent
- Sophia Taylor and
- Scott T. Handy
Beilstein J. Org. Chem. 2024, 20, 2217–2224, doi:10.3762/bjoc.20.189
- application of simple, inexpensive, and recyclable deep eutectic solvents to the allylation of carbonyls. While several sets of conditions were developed, the goal of avoiding stoichiometric amounts of metal has proven elusive. Still, a deep eutectic solvent can be used to plate out and thus recover the metal
- used, offering an interesting new option for electrochemical allylations. Keywords: allylation; electrosynthesis; eutectic solvent; recycling; tin; Introduction The last several years have witnessed a tremendous resurgence of interest in electrochemistry in the area of organic synthesis [1]. While
- solvents Tetrabutylammonium bromide/ethylene glycol (1:3 molar ratio) deep eutectic solvent To 8.0 grams of tetrabutylammonium bromide (TBAB) were added 4.7 grams of ethylene glycol (EG). The resulting mixture was heated to 70 °C until a homogeneous liquid formed. It was stored at this same temperature
Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles
- Periklis X. Kolagkis,
- Eirini M. Galathri and
- Christoforos G. Kokotos
Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36
Graphical Abstract
Scheme 1: Examples of BIMs used for their medicinal properties.
Scheme 2: Mechanisms for the synthesis of BIMs using protic or Lewis acids as catalysts.
Scheme 3: Synthesis of bis(indolyl)methanes using DBDMH.
Scheme 4: Competition experiments and synthesis of bis(indolyl)methanes using DBDMH.
Scheme 5: Proposed mechanism for formation of BIM of using DBDMH.
Scheme 6: Synthesis of bis(indolyl)methanes using I2.
Scheme 7: General reaction mechanism upon halogen bonding.
Scheme 8: Synthesis of bis(indolyl)methanes using I2, introduced by Ji.
Scheme 9: Synthesis of bis(indolyl)methanes using Br2 in CH3CN.
Scheme 10: Βidentate halogen-bond donors.
Scheme 11: Synthesis of bis(indolyl)methanes using bidentate halogen-bond donor 26.
Scheme 12: Proposed reaction mechanism.
Scheme 13: Synthesis of bis(indolyl)methanes using iodoalkyne as catalyst.
Scheme 14: Proposed reaction mechanism.
Scheme 15: Optimized reaction conditions used by Ramshini.
Scheme 16: Activation of the carbonyl group by HPA/TPI-Fe3O4.
Scheme 17: Synthesis of BIMs in the presence of nanoAg-Pt/SiO2-doped silicate.
Scheme 18: Mechanism of action proposed by Khalafi-Nezhad et al.
Scheme 19: Activation of the carbonyl group by the Cu–isatin Schiff base complex.
Scheme 20: Optimum reaction conditions published by Jain.
Scheme 21: Organocatalytic protocol utilizing nanoparticles introduced by Bankar.
Scheme 22: Activation of the carbonyl group by the AlCl3·6H2O-SDS-SiO2 complex.
Scheme 23: Optimal reaction conditions for the aforementioned nano-Fe3O4 based catalysts.
Scheme 24: Nanocatalytic protocol proposed by Kaur et al.
Scheme 25: Microwave approach introduced by Yuan.
Scheme 26: Microwave approach introduced by Zahran et al.
Scheme 27: Microwave irradiation protocol introduced by Bindu.
Scheme 28: Silica-supported microwave irradiation protocol.
Scheme 29: Proposed mechanism for formation of BIM by Nongkhlaw.
Scheme 30: Microwave-assisted synthesis of BIMs catalyzed by succinic acid.
Scheme 31: Proposed mechanism of action of MMO-4.
Scheme 32: Catalytic approach introduced by Muhammadpoor-Baltork et al.
Scheme 33: Reaction conditions used by Xiao-Ming.
Scheme 34: Ultrasonic irradiation-based protocol published by Saeednia.
Scheme 35: Pyruvic acid-mediated synthesis of BIMs proposed by Thopate.
Scheme 36: Synthesis of BIMs using [bmim]BF4 or [bmim]PF6 ionic liquids.
Scheme 37: Synthesis of BIMs utilizing In(OTf)3 in octylmethylimidazolium hexafluorophosphate as ionic liquid.
Scheme 38: FeCl3·6H2O-catalyzed synthesis of BIMs with use of ionic liquid.
Scheme 39: Synthesis of BIMs utilizing the [hmim]HSO4/EtOH catalytic system.
Scheme 40: Synthesis of BIMs utilizing acidic ionic liquid immobilized on silica gel (ILIS-SO2Cl).
Scheme 41: The [bmim][MeSO4]-catalyzed reaction of indole with various aldehydes.
Scheme 42: The role of [bmim][MeSO4] in catalyzing the reaction of indole with aldehydes.
Scheme 43: Synthesis of BIMs utilizing FeCl3-based ionic liquid ([BTBAC]Cl-FeCl3) as catalyst.
Scheme 44: Synthesis of BIMs using [Msim]Cl at room temperature.
Scheme 45: [Et3NH][H2PO4]-catalyzed synthesis of bis(indolyl)methanes.
Scheme 46: PILs-catalyzed synthesis of bis(indolyl)methanes.
Scheme 47: FSILs-mediated synthesis of bis(indolyl)methanes.
Scheme 48: Possible “release and catch” catalytic process.
Scheme 49: Synthesis of bis(indolyl)methanes by [DABCO-H][HSO4].
Scheme 50: Synthesis of bis(indolyl)methanes by [(THA)(SO4)].
Scheme 51: Synthesis of BBSI-Cl and BBSI-HSO4.
Scheme 52: Synthesis of BIMs in the presence of BBSI-Cl and BBSI-HSO4.
Scheme 53: Chemoselectivity of the present method.
Scheme 54: Synthesis of BIMs catalyzed by chitosan-supported ionic liquid.
Scheme 55: Proposed mechanism of action of CSIL.
Scheme 56: Optimization of the reaction in DESs.
Scheme 57: Synthesis of BIMs using ChCl/SnCl2 as DES.
Scheme 58: Synthesis of BIMs derivatives in presence of DES.
Scheme 59: BIMs synthesis in choline chloride/urea (CC/U).
Scheme 60: Flow chemistry-based synthesis of BIMs by Ley.
Scheme 61: Flow chemistry-based synthesis of BIMs proposed by Nam et al.
Scheme 62: Amino-catalyzed reaction of indole with propionaldehyde.
Scheme 63: Aminocatalytic synthesis of BIMs.
Scheme 64: Proposed mechanism for the aminocatalytic synthesis of BIMs.
Scheme 65: Enzymatic reaction of indole with aldehydes.
Scheme 66: Proposed mechanism for the synthesis of BIMs catalyzed by TLIM.
Scheme 67: Proposed reaction mechanism by Badsara.
Scheme 68: Mechanism proposed by D’Auria.
Scheme 69: Photoinduced thiourea catalysis.
Scheme 70: Proposed mechanism of photoacid activation.
Scheme 71: Proposed mechanism of action for CF3SO2Na.
Scheme 72: Proposed mechanism for the synthesis of BIMs by Mandawad.
Scheme 73: Proposed mechanism for the (a) acid generation and (b) synthesis of BIMs.
Scheme 74: a) Reaction conditions employed by Khaksar and b) activation of the carbonyl group by HFIP.
Scheme 75: Activation of the carbonyl group by the PPy@CH2Br through the formation of a halogen bond.
Scheme 76: Reaction conditions utilized by Mhaldar et al.
Scheme 77: a) Reaction conditions employed by López and b) activation of the carbonyl group by thiourea.
Scheme 78: Infrared irradiation approach introduced by Luna-Mora and his research group.
Scheme 79: Synthesis of BIMs with the use of the Fe–Zn BMOF.
Synthesis of 5-arylidenerhodanines in L-proline-based deep eutectic solvent
- Stéphanie Hesse
Beilstein J. Org. Chem. 2023, 19, 1537–1544, doi:10.3762/bjoc.19.110
- scaffolds is the introduction of a benzylidene moiety on C5 via a Knoevenagel reaction. Here, a facile synthesis of 5-arylidenerhodanines via a Knoevenagel reaction in an ʟ-proline-based deep eutectic solvent (DES) is reported. This method is fast (1 h at 60 °C), easy, catalyst-free and sustainable as no
- compounds are the more active ones. Keywords: antioxidant; deep eutectic solvent; Knoevenagel; ʟ-proline DES; rhodanine; Introduction Rhodanines and related five-membered heterocycles with multiple heteroatoms (i.e., thiazolidinediones, thiazolidinones, hydantoins, thiohydantoins) are very interesting
- eutectic solvent. Indeed, Pro/Gly (1:2) was the most effective DES compared to classical ChCl/Gly and ChCl/urea. It allowed formation of the expected products in very good yields at mild temperature (60 °C), and in most cases within only one hour of reaction. Heteroaromatic aldehydes as well as
Graphical Abstract
Figure 1: Examples of rhodanines and related five-membered heterocycles with interesting biological activitie...
Scheme 1: Synthesis of 5-benzylidenerhodanine derivatives. Conditions: areaction performed for 3 h at 60 °C. b...
Clauson–Kaas pyrrole synthesis using diverse catalysts: a transition from conventional to greener approach
- Dileep Kumar Singh and
- Rajesh Kumar
Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71
- synthesis of N-substituted pyrroles 29 in the yields of 85–97% using squaric acid as catalyst. In this reaction, various amines 28 and 2,5-DMTHF (2) were reacted in greener solvents like water, deep eutectic solvent (DEC) and polyethylene glycol (PEG) under thermal or ultrasonic irradiation (Scheme 13a
- amines 52 with 2,5-DMTHF (2) under a L-(+)-tartaric acid-choline chloride based deep eutectic solvent as green medium (Scheme 25a). Deep eutectic solvents (DESs) are mainly synthesized by mixing quaternary ammonium salts and hydrogen-bond donors. In this study, various combinations of salts and hydrogen
- process has many advantages because it is a metal-free, easy to use, and environmentally friendly method that also gives good product yields with a wide range of substrates. The deep eutectic solvent used in this protocol is cheap, reusable, non-toxic, and biodegradable. In this study, it was found that
Graphical Abstract
Figure 1: Various pyrrole containing molecules.
Scheme 1: Various synthestic protocols for the synthesis of pyrroles.
Figure 2: A tree-diagram showing various conventional and green protocols for Clauson-Kaas pyrrole synthesis.
Scheme 2: A general reaction of Clauson–Kaas pyrrole synthesis and proposed mechanism.
Scheme 3: AcOH-catalyzed synthesis of pyrroles 5 and 7.
Scheme 4: Synthesis of N-substituted pyrroles 9.
Scheme 5: P2O5-catalyzed synthesis of N-substituted pyrroles 11.
Scheme 6: p-Chloropyridine hydrochloride-catalyzed synthesis of pyrroles 13.
Scheme 7: TfOH-catalyzed synthesis of N-sulfonylpyrroles 15, N-sulfonylindole 16, N-sulfonylcarbazole 17.
Scheme 8: Scandium triflate-catalyzed synthesis of N-substituted pyrroles 19.
Scheme 9: MgI2 etherate-catalyzed synthesis and proposed mechanism of N-arylpyrrole derivatives 21.
Scheme 10: Nicotinamide catalyzed synthesis of pyrroles 23.
Scheme 11: ZrOCl2∙8H2O catalyzed synthesis and proposed mechanism of pyrrole derivatives 25.
Scheme 12: AcONa catalyzed synthesis of N-substituted pyrroles 27.
Scheme 13: Squaric acid-catalyzed synthesis and proposed mechanism of N-substituted pyrroles 29.
Figure 3: Reusability of catalyst γ-Fe2O3@SiO2-Sb-IL in six cycles.
Scheme 14: Magnetic nanoparticle-supported antimony catalyst used in the synthesis of N-substituted pyrroles 31...
Scheme 15: Iron(III) chloride-catalyzed synthesis of N-substituted pyrroles 33.
Scheme 16: Copper-catalyzed Clauson–Kaas synthesis and mechanism of pyrroles 35.
Scheme 17: β-CD-SO3H-catalyzed synthesis and proposed mechanism of pyrroles 37.
Figure 4: Recyclability of β-cyclodextrin-SO3H.
Scheme 18: Solvent-free and catalyst-free synthesis and plausible mechanism of N-substituted pyrroles 39.
Scheme 19: Nano-sulfated TiO2-catalyzed synthesis of N-substituted pyrroles 41.
Figure 5: Plausible mechanism for the formation of N-substituted pyrroles catalyzed by nano-sulfated TiO2 cat...
Scheme 20: Copper nitrate-catalyzed Clauson–Kaas synthesis and mechanism of N-substituted pyrroles 43.
Scheme 21: Synthesis of N-substituted pyrroles 45 by using Co catalyst Co/NGr-C@SiO2-L.
Scheme 22: Zinc-catalyzed synthesis of N-arylpyrroles 47.
Scheme 23: Silica sulfuric acid-catalyzed synthesis of pyrrole derivatives 49.
Scheme 24: Bismuth nitrate-catalyzed synthesis of pyrroles 51.
Scheme 25: L-(+)-tartaric acid-choline chloride-catalyzed Clauson–Kaas synthesis and plausible mechanism of py...
Scheme 26: Microwave-assisted synthesis of N-substituted pyrroles 55 in AcOH or water.
Scheme 27: Synthesis of pyrrole derivatives 57 using a nano-organocatalyst.
Figure 6: Nano-ferric supported glutathione organocatalyst.
Scheme 28: Microwave-assisted synthesis of N-substituted pyrroles 59 in water.
Scheme 29: Iodine-catalyzed synthesis and proposed mechanism of pyrroles 61.
Scheme 30: H3PW12O40/SiO2-catalyzed synthesis of N-substituted pyrroles 63.
Scheme 31: Fe3O4@-γ-Fe2O3-SO3H-catalyzed synthesis of pyrroles 65.
Scheme 32: Mn(NO3)2·4H2O-catalyzed synthesis and proposed mechanism of pyrroles 67.
Scheme 33: p-TsOH∙H2O-catalyzed (method 1) and MW-assisted (method 2) synthesis of N-sulfonylpyrroles 69.
Scheme 34: ([hmim][HSO4]-catalyzed Clauson–Kaas synthesis of pyrroles 71.
Scheme 35: Synthesis of N-substituted pyrroles 73 using K-10 montmorillonite catalyst.
Scheme 36: CeCl3∙7H2O-catalyzed Clauson–Kaas synthesis of pyrroles 75.
Scheme 37: Synthesis of N-substituted pyrroles 77 using Bi(NO3)3∙5H2O.
Scheme 38: Oxone-catalyzed synthesis and proposed mechanism of N-substituted pyrroles 79.
Valorisation of plastic waste via metal-catalysed depolymerisation
- Francesca Liguori,
- Carmen Moreno-Marrodán and
- Pierluigi Barbaro
Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53
- filtration and reused. As an alternative to ILs, metal-based deep eutectic solvent (DES) systems were also explored as catalysts for the glycolysis reaction of PET using EG. DES have similar properties to metallated ILs, but they are cheaper and less toxic [232][233]. Because of this, they have found
Graphical Abstract
Figure 1: Potential classification of plastic recycling processes. The area covered by the present review is ...
Figure 2: EG produced during glycolytic depolymerisation of PET using DEG + DPG as solvent and titanium(IV) n...
Scheme 1: Simplified representation of the conversion of 1,4-PBD to C16–C44 macrocycles using Ru metathesis c...
Figure 3: Main added-value monomers obtainable by catalytic depolymerisation of PET via chemolytic methods.
Scheme 2: Hydrogenolytic depolymerisation of PET by ruthenium complexes.
Scheme 3: Depolymerisation of PET via catalytic hydrosilylation by Ir(III) pincer complex.
Scheme 4: Catalytic hydrolysis (top) and methanolysis (bottom) reactions of PET.
Scheme 5: Depolymerisation of PET by glycolysis with ethylene glycol.
Figure 4: Glycolysis of PET: evolution of BHET yield over time, with and without zinc acetate catalyst (196 °...
Scheme 6: Potential activated complex for the glycolysis reaction of PET catalysed by metallated ILs and evol...
Scheme 7: One-pot, two-step process for PET repurposing via chemical recycling.
Scheme 8: Synthetic routes to PLA.
Scheme 9: Structures of the zinc molecular catalysts used for PLA-methanolysis in various works. a) See [265], b) ...
Scheme 10: Depolymerisation of PLLA by Zn–N-heterocyclic carbene complex.
Scheme 11: Salalen ligands.
Scheme 12: Catalytic hydrogenolysis of PLA.
Scheme 13: Catalytic hydrosilylation of PLA.
Scheme 14: Hydrogenative depolymerisation of PBT and PCL by molecular Ru catalysts.
Scheme 15: Glycolysis reaction of PCT by diethylene glycol.
Scheme 16: Polymerisation–depolymerisation cycle of 3,4-T6GBL.
Scheme 17: Polymerisation–depolymerisation cycle of 2,3-HDB.
Scheme 18: Hydrogenative depolymerisation of PBPAC by molecular Ru catalysts.
Scheme 19: Catalytic hydrolysis (top), alcoholysis (middle) and aminolysis (bottom) reactions of PBPAC.
Scheme 20: Hydrogenative depolymerisation of PPC (top) and PEC (bottom) by molecular Ru catalysts.
Scheme 21: Polymerisation-depolymerisation cycle of BEP.
Scheme 22: Hydrogenolysis of polyamides using soluble Ru catalysts.
Scheme 23: Catalytic depolymerisation of epoxy resin/carbon fibres composite.
Scheme 24: Depolymerisation of polyethers with metal salt catalysts and acyl chlorides.
Scheme 25: Proposed mechanism for the iron-catalysed depolymerisation reaction of polyethers. Adapted with per...
Towards the development of continuous, organocatalytic, and stereoselective reactions in deep eutectic solvents
- Davide Brenna,
- Elisabetta Massolo,
- Alessandra Puglisi,
- Sergio Rossi,
- Giuseppe Celentano,
- Maurizio Benaglia and
- Vito Capriati
Beilstein J. Org. Chem. 2016, 12, 2620–2626, doi:10.3762/bjoc.12.258
- Mangiagalli 25, 20133 Milano, Italy Dipartimento di Farmacia–Scienze del Farmaco, Università di Bari “Aldo Moro”, Consorzio C.I.N.M.P.I.S., Via E. Orabona 4, I-70125 Bari, Italy 10.3762/bjoc.12.258 Abstract Different deep eutectic solvent (DES) mixtures were studied as reaction media for the continuous
Graphical Abstract
Scheme 1: L-Proline-promoted stereoselective aldol reaction in DES.
Figure 1: Experimental set-up I: test tube (d = 0.5 cm); flow 1 mL/min; DES (1.5 mL); L-proline/DES = 130 mg/...
Scheme 2: Aldol reaction under continuous flow conditions in DESs.
