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Search for "amide activation" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.
Recent advances in the cleavage of non-activated amides
- Eun-Sol Choi and
- Hyo-Jun Lee
Beilstein J. Org. Chem. 2026, 22, 352–369, doi:10.3762/bjoc.22.23
- . Keywords: amide; amide activation; esterification; non-activated amide; transamidation; Introduction Serving as a cornerstone in organic chemistry, the amide bond is a fundamental and extensively utilized functional group, playing a central role in natural products, biomolecules, and functional materials
- corresponding products 213–218 in moderate yields. Remarkably, in all cases, the otherwise bulky and less reactive amide was preferentially cleaved over less-hindered and more electrophilic functionalities, demonstrating unusual and highly valuable chemoselectivity in amide activation and transformation
Graphical Abstract
Scheme 1: a) Resonance structure of amide. b) Concept of twisted amides. c) Transition-metal-catalyzed activa...
Scheme 2: Esterification of amides catalyzed by CeO2.
Scheme 3: Hydrolysis of amides catalyzed by Nb2O5.
Scheme 4: Manganese-catalyzed esterification of tertiary amides.
Scheme 5: Tungsten-catalyzed transamidation of hindered tertiary amides.
Scheme 6: Palladium-catalyzed transamidation of amides.
Scheme 7: Synthesis of benzyl esters via electrophilic activation of amides using DPT-BM.
Scheme 8: Esterification of amides promoted by SO2F2.
Scheme 9: α-Fluorinative cleavage of pyrrolidine-based tertiary amides via double electrophilic activation wi...
Scheme 10: Esterification of primary amides using TCCA via the generation of RCONCl2.
Scheme 11: Esterification of amides via electrophilic activation with Me2SO4.
Scheme 12: HBF4-mediated esterification of amides.
Scheme 13: Synthesis of 2,2,2-trifluoroethyl esters via electrophilic esterification of amide promoted by 67.
Scheme 14: Electrochemical activation of C–N bonds for esterification.
Scheme 15: Catalyst- and reagent-free transamidation of amide using aniline hydrochloride salt.
Scheme 16: CO2-catalyzed transamidation of amides.
Scheme 17: Transamidation of formamides using cyclic dihydrogen tetrametaphosphate.
Scheme 18: BF3·OEt2-mediated transamidation of primary amides.
Scheme 19: Acyl iodide intermediate 121 generation from amides for the transamidation using HOTf and KI.
Scheme 20: Esterification of N,N-dimethyl amides via electrophilic generation of acyl iodide intermediates.
Scheme 21: Transamidation of DMAc promoted by KOt-Bu.
Scheme 22: a) LiHMDS-mediated transamidation of tertiary amides. b) Computed reactivities of selected amides. ...
Scheme 23: Zn-catalyzed chemoselective cleavage of amides directed by tert-butyl nicotinate.
Scheme 24: Chemoselective cleavage of N-PMB anilide for transamidation via acyl fluoride 194 generation. a) Cu...
Pyridine C(sp2)–H bond functionalization under transition-metal and rare earth metal catalysis
- Haritha Sindhe,
- Malladi Mounika Reddy,
- Karthikeyan Rajkumar,
- Akshay Kamble,
- Amardeep Singh,
- Anand Kumar and
- Satyasheel Sharma
Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62
- 205 were accessed in moderate to excellent yields and also naphthyridine derivatives (205k and 205l) were synthesized. In the proposed mechanism, the initial deprotonation of HNBn2 by Ln[N(TMS)2]3 provided the lanthanide amide. Activation of the vinyl-substituted pyridin-3-amine 204 by the lanthanide
Graphical Abstract
Figure 1: Representative examples of bioactive natural products and FDA-approved drugs containing a pyridine ...
Scheme 1: Classical and traditional methods for the synthesis of functionalized pyridines.
Scheme 2: Rare earth metal (Ln)-catalyzed pyridine C–H alkylation.
Scheme 3: Pd-catalyzed C–H alkylation of pyridine N-oxide.
Scheme 4: CuI-catalyzed C–H alkylation of N-iminopyridinium ylides with tosylhydrazones (A) and a plausible r...
Scheme 5: Zirconium complex-catalyzed pyridine C–H alkylation.
Scheme 6: Rare earth metal-catalyzed pyridine C–H alkylation with nonpolar unsaturated substrates.
Scheme 7: Heterobimetallic Rh–Al complex-catalyzed ortho-C–H monoalkylation of pyridines.
Scheme 8: Mono(phosphinoamido)-rare earth complex-catalyzed pyridine C–H alkylation.
Scheme 9: Rhodium-catalyzed pyridine C–H alkylation with acrylates and acrylamides.
Scheme 10: Ni–Al bimetallic system-catalyzed pyridine C–H alkylation.
Scheme 11: Iridium-catalyzed pyridine C–H alkylation.
Scheme 12: para-C(sp2)–H Alkylation of pyridines with alkenes.
Scheme 13: Enantioselective pyridine C–H alkylation.
Scheme 14: Pd-catalyzed C2-olefination of pyridines.
Scheme 15: Ru-catalyzed C-6 (C-2)-propenylation of 2-arylated pyridines.
Scheme 16: C–H addition of allenes to pyridines catalyzed by half-sandwich Sc metal complex.
Scheme 17: Pd-catalyzed stereodivergent synthesis of alkenylated pyridines.
Scheme 18: Pd-catalyzed ligand-promoted selective C3-olefination of pyridines.
Scheme 19: Mono-N-protected amino acids in Pd-catalyzed C3-alkenylation of pyridines.
Scheme 20: Amide-directed and rhodium-catalyzed C3-alkenylation of pyridines.
Scheme 21: Bimetallic Ni–Al-catalyzed para-selective alkenylation of pyridine.
Scheme 22: Arylboronic ester-assisted pyridine direct C–H arylation.
Scheme 23: Pd-catalyzed C–H arylation/benzylation with toluene.
Scheme 24: Pd-catalyzed pyridine C–H arylation with potassium aryl- and heteroaryltrifluoroborates.
Scheme 25: Transient activator strategy in pyridine C–H biarylation.
Scheme 26: Ligand-promoted C3-arylation of pyridine.
Scheme 27: Pd-catalyzed arylation of nicotinic and isonicotinic acids.
Scheme 28: Iron-catalyzed and imine-directed C–H arylation of pyridines.
Scheme 29: Pd–(bipy-6-OH) cooperative system-mediated direct pyridine C3-arylation.
Scheme 30: Pd-catalyzed pyridine N-oxide C–H arylation with heteroarylcarboxylic acids.
Scheme 31: Pd-catalyzed C–H cross-coupling of pyridine N-oxides with five-membered heterocycles.
Scheme 32: Cu-catalyzed dehydrative biaryl coupling of azine(pyridine) N-oxides and oxazoles.
Scheme 33: Rh(III)-catalyzed cross dehydrogenative C3-heteroarylation of pyridines.
Scheme 34: Pd-catalyzed C3-selective arylation of pyridines.
Scheme 35: Rhodium-catalyzed oxidative C–H annulation of pyridines to quinolines.
Scheme 36: Rhodium-catalyzed and NHC-directed C–H annulation of pyridine.
Scheme 37: Ni/NHC-catalyzed regio- and enantioselective C–H cyclization of pyridines.
Scheme 38: Rare earth metal-catalyzed intramolecular C–H cyclization of pyridine to azaindolines.
Scheme 39: Rh-catalyzed alkenylation of bipyridine with terminal silylacetylenes.
Scheme 40: Rollover cyclometallation in Rh-catalyzed pyridine C–H functionalization.
Scheme 41: Rollover pathway in Rh-catalyzed C–H functionalization of N,N,N-tridentate chelating compounds.
Scheme 42: Pd-catalyzed rollover pathway in bipyridine-6-carboxamides C–H arylation.
Scheme 43: Rh-catalyzed C3-acylmethylation of bipyridine-6-carboxamides with sulfoxonium ylides.
Scheme 44: Rh-catalyzed C–H functionalization of bipyridines with alkynes.
Scheme 45: Rh-catalyzed C–H acylmethylation and annulation of bipyridine with sulfoxonium ylides.
Scheme 46: Iridium-catalyzed C4-borylation of pyridines.
Scheme 47: C3-Borylation of pyridines.
Scheme 48: Pd-catalyzed regioselective synthesis of silylated dihydropyridines.
Direct synthesis of anomeric tetrazolyl iminosugars from sugar-derived lactams
- Michał M. Więcław and
- Bartłomiej Furman
Beilstein J. Org. Chem. 2021, 17, 115–123, doi:10.3762/bjoc.17.12
- of benzoic acid at an elevated temperature yielding lactam 6 almost quantitatively. The deoxygenative reduction of this compound turned out to be challenging, as the typical procedure using LiAlH4 proved ineffective. We were able to obtain 7 using a Schwartz’s reagent-mediated amide activation
Graphical Abstract
Scheme 1: Our previous efforts in the field of functionalization of sugar-derived lactams.
Figure 1: Key concepts behind the goal of this work [34].
Scheme 2: Preliminary experiment in search of a procedure for the synthesis of 2-(1H-tetrazol-5-yl)-iminosuga...
Scheme 3: Synthesis of a new class of alkaloid scaffold using the presented methodology.
Scheme 4: Synthesis of a new, chiral 2-(tetrazol-5-yl)-iminosugar based potential organocatalyst.
Scheme 5: Principle behind Woerpel’s model for prediction of the direction of nucleophile addition to oxocarb...
Scheme 6: Difference in conformational stability of glucose- and galactose-derived iminium cations and the maj...
Figure 2: ORTEP structures of compounds 3a and 3e obtained by X-ray analysis. Hydrogen atoms and benzyl group...
Figure 3: Proposed structures of compounds 5a and 2-epi-5a with 1H-1H couplings and NOE effects shown.
Scheme 7: Proposed reaction mechanism for the described Ugi–azide reaction variant.
Scheme 8: Possible pathway for spontaneous imine formation. Values reported are in kcal·mol−1.
Scheme 9: A possible path for tetrazole formation in the described conditions. Values reported are in kcal·mol...
Cyclisation mechanisms in the biosynthesis of ribosomally synthesised and post-translationally modified peptides
- Andrew W. Truman
Beilstein J. Org. Chem. 2016, 12, 1250–1268, doi:10.3762/bjoc.12.120
- to AMP and pyrophosphate [43]. The function of this highly conserved “non-TOMM” protein has yet to be identified, but it indicates that amide activation by ATP may not be confined to the biosynthesis of secondary metabolites or purines. Ec-YcaO also lacks a partner C-protein, which is also the case
Graphical Abstract
Figure 1: Schematic of RiPP biosynthesis. Thiazole/oxazole formation is represented by the blue heterocycle (...
Figure 2: Examples of heterocycles in RiPPs alongside the precursor peptides that these molecules derive from...
Figure 3: Formation of thiazoles and oxazoles in RiPPs. A) Biosynthesis of microcin B17. B) Mechanistic model...
Figure 4: Lanthionine bond formation. A) Nisin and its precursor peptide. B) Mechanism of lanthionine bond fo...
Figure 5: S-[(Z)-2-Aminovinyl]-D-cysteine (AviCys) formation in the epidermin pathway. A) Mechanisms for deca...
Figure 6: Cyclisation in the biosynthesis of thiopeptides. A) Mechanism of TclM-catalysed heterocyclisation i...
Figure 7: ATP-dependent macrocyclisation. A) General mechanism for ATP-dependent macrolactonisation or macrol...
Figure 8: Peptidase-like macrolactam formation. A) General mechanism. B) Examples of RiPPs cyclised by serine...
Figure 9: Structure of autoinducing peptide AIP-I from Staphylococcus aureus and the sequence of the correspo...
Figure 10: Radical cyclisation in RiPP biosynthesis. A) AlbA-catalysed formation of thioethers in the biosynth...
Figure 11: RiPPs with uncharacterised mechanisms of cyclisation. Unusual heterocycles in ComX and methanobacti...
