The reaction centers around an imine - lithium enolate cycloaddition. (wikipedia.org)
Both imine and enole intermediate join in a cycloaddition reaction followed by an intramolecular nucleophilic acyl substitution of the amine with expulsion of the chiral auxiliary to the cis-lactam. (wikipedia.org)
A convenient Kinugasa reaction protocol enables a one-pot synthesis of 4-substituted β-lactams from inexpensive calcium carbide and nitrone derivatives. (organic-chemistry.org)
The reaction provides rapid access to practical quantities of β-lactams substituted at position 4. (organic-chemistry.org)
A catalytic, highly diastereoselective synthesis of trans -β-lactams is based on a phosphonium fluoride precatalyst that both activates the nucleophile and directs the reaction process for high yield and diastereoselectivity. (organic-chemistry.org)
A chiral N-heterocyclic carbene catalyzed the Staudinger reaction of arylalkylketenes with a variety of N -tert-butoxycarbonyl arylimines to give the corresponding cis -β-lactams in good yields with good diastereoselectivities and excellent enantioselectivities. (organic-chemistry.org)
A catalytic enantioselective Staudinger reaction is described that preferentially furnishes trans β-lactams. (organic-chemistry.org)
A practical methodology for the catalytic, asymmetric synthesis of β-lactams results from the development of a catalyzed reaction of ketenes (or their derived zwitterionic enolates) and imines using benzoylquinine as chiral catalyst and proton sponge as the stoichiometric base. (organic-chemistry.org)
The aza-oxyallyl cations generated by dehydrohalogenation form α-halohydroxamates underwent (3+2) cycloaddition reaction with substituted indoles. (unr.edu)
The developed reaction features good functional group tolerance, broad substrate scope, and operational simplicity, enabling efficient assembly of a wide range of 3,3-difluoro-γ-lactam derivatives bearing an O-substituted quaternary carbon center in moderate to good yields. (bvsalud.org)
Depending on the specific azetidin-2-one C4 substituent, this reaction was shown to selectively produce 3-imino-β-lactams (through dehydration), α-aminoamides (through CO elimination) or ethanediamides (through an unprecedented C3-C4 ring opening). (ugent.be)
Treatment of 2,3-dihydro-2-methyl-3-phenyl-1 H -pyrazino[3,4,5- cd ]indolizine 2-oxides ( 5 ) with trifluoroacetic anhydride gave new heterocyclic six-membered betaines ( 6 ) which underwnet 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate and maleimides in hot toluene to yield the corresponding cycloadducts ( 7 ) and ( 8 ). (heterocycles.jp)
Mbadcam, J.K. Molecular Electron Density Theory Study of Fused Regioselectivity in the Intramolecular [3+2] Cycloaddition Reaction of Nitrones. (luisrdomingo.com)
Steric interactions controlling the syn diastereofacial selectivity in the [3+2] cycloaddition reaction between acetonitrile axide and 7-oxanorborn-5-en-2-ones. (luisrdomingo.com)
A highly efficient visible-light-mediated photochemical [2 + 2] cycloaddition is coupled with an atom economic thermal cascade reaction in a continuous flow process. (uniqsis.com)
Intramolecular2
Following our groups' previous discovery, intramolecular aza-(4+3) cycloadditions of such transient intermediates generated by the dehydrohalogenation of corresponding α-halohydroxamates with furan and N-Boc pyrroles were developed. (unr.edu)
Here we were able to demonstrate the extended scope of the intramolecular aza-(4+3) cycloaddition reactions of allylic cations to generate macrocyclic motifs. (unr.edu)
Reactions14
Thermally promoted reactions of α-acyl-α-diazoacetates with imines deliver α-alkoxycarbonyl-substituted β-lactams with outstanding diastereoselectivity. (organic-chemistry.org)
Cycloaddition reactions are powerful transformations for the construction of various cyclic organic molecules. (unr.edu)
Cycloaddition reactions of oxyallyl cations are widely studied and applied in the synthesis of various natural products. (unr.edu)
α-Halohydroxamates with two reacting termini separated by tether chains of three to six atoms underwent cycloaddition reactions successfully to provide unique tricyclic and polycyclic lactams in good yields. (unr.edu)
Getting inspired from the previous (3+2) cycloaddition reactions of indoles, we further expanded this reactivity in other carbonyl compounds. (unr.edu)
Unveiling the Role of the Strain of Cyclohexyne in [3+2] Cycloaddition Reactions through the Molecular Electron Density Theory. (luisrdomingo.com)
P. A Molecular Electron Density Theory Study of the Role of the Copper-Metallation of Azomethine Ylides in [3+2] Cycloaddition Reactions. (luisrdomingo.com)
P. A Molecular Electron Density Theory Study of the Reactivity and Selectivities in [3+2] Cycloaddition Reactions of C,N-Dialkyl Nitrones with Ethylene Derivatives. (luisrdomingo.com)
Understanding the Reactivity and Regioselectivity of [3+2] Cycloaddition Reactions between Substituted Nitrile Oxides and Methyl Acrylate. (luisrdomingo.com)
Ríos-Gutiérrez, M . A. Molecular Electron Density Theory Study of the Reactivity of Azomethine Imine in [3+2] Cycloaddition Reactions. (luisrdomingo.com)
Pérez, P . How does the Global Electron Density Transfer Diminish Activation Energies in Polar Cycloaddition Reactions? (luisrdomingo.com)
P . An MEDT study of the carbenoid-type [3+2] cycloaddition reactions of nitrile ylides with electron-deficient chiral oxazolidinones. (luisrdomingo.com)
P. A new model for C-C bond formation processes derived from the Molecular Electron-Density Theory in the study of the mechanism of [3+2] cycloaddition reactions of carbenoid nitrile ylides with electron-deficient ethylenes. (luisrdomingo.com)
Domingo, L.R. Unravelling the Mysteries of the [3+2] Cycloaddition Reactions. (luisrdomingo.com)
Derivatives1
The utility of these cyclopropanone surrogates is demonstrated in a mild and stereospecific formal [3+1] cycloaddition with simple hydroxylamines acting here as nitrene equivalents, leading to the efficient formation of chiral β-lactam derivatives. (chemrxiv.org)
Bicyclic1
Hitherto unknown or rarely reported sulfur-containing bicyclic β-lactams, 6- and 7-thianonanams, were synthesized by addition of sulfur dichloride to N -allyl-β-styryl-β-lactam. (heterocycles.jp)
Chiral1
In order to ensure the correct stereochemistry (the phenyl group and the silyl ether must adopt a cis configuration) in the β-lactam a chiral auxiliary is used in the enolate synthesis. (wikipedia.org)
Molecules1
Those polycyclic lactams were further transformed into an array of functionalized molecules including polyhydroxylated azepane derivates.Macrocycles are an important class of compounds having conformational flexibility with potential bioactivity. (unr.edu)
Ethers1
Asymmetric Synthesis of α,α-Disubstituted Amino Acids by Cycloaddition of (E)-Ketonitrones with Vinyl Ethers. (univ-grenoble-alpes.fr)
Amino acids2
Various trans -substituted β-lactams derived from amino acids have been prepared. (organic-chemistry.org)
1,3-Dipolar Cycloadditions: A Regio and Stereoselective Tool to Reach Unnatural Quaternary Amino Acids , Dujardin, G , Zhang X , Py Sandrine , Poisson Jean-François , Laurent M Y. , and Martel A , J. Pept. (univ-grenoble-alpes.fr)
Yields2
The resulting rhodium enolate reacted as a Reformatsky-type reagent with various imines to give syn -β-lactams in good to excellent yields with high diastereoselectivity. (organic-chemistry.org)
The reactive intermediates were efficiently trapped by dienophiles, such as N -phenylmaleimide and diethyl azodicarboxylate, to form [4+2] cycloaddition products in high yields. (heterocycles.jp)
Imine2
The Staudinger synthesis, an overall [2 + 2] cycloaddition of a ketene with an imine, provides a nicely convergent route to biologically and synthetically interesting β-lactams. (organic-chemistry.org)
Developing methods to detect pesticide residues in food products via HPLC, Synthesising and testing novel β-Lactams via Staudinger Ketene-imine cycloadditions and my MChem project working under supervision of Dr George Weaver - Synthesising fluorinated benzothiazoles as anti- trypanosomiasis agents. (leeds.ac.uk)
Cation1
Our group's interest in generating electrophilic nitrogen species led us to generate aza-analog of such allylic cation intermediate to provide easy access to seven-membered lactams. (unr.edu)
Iminocyclopropanes were converted into functionalised aminocyclopropanes in the presence of functionalised alkenes in a formal [3+2] cycloaddition. (uniqsis.com)
Quantities1
The PhotoSyn was utilised to demonstrate that this process is readily scalable in continuous flow to provide access to decagram quantities of valuable gamma-lactams and azaspirocycles, for application in drug discovery. (uniqsis.com)
Organic1
The Ojima lactam is an organic compound of some importance in the commercial production of Taxol. (wikipedia.org)
Radical1
A diethylzinc-mediated radical (3 + 2) cycloaddition of vinyl azides with ethyl iododifluoroacetate is presented. (bvsalud.org)
Approach3
We have successfully developed the new method for pyrroloindolines synthesis utilizing (3+2) cycloaddition approach. (unr.edu)
Neil K. Garg of UCLA devised an approach to 4 based on the generation of the cyclic allene from 1 , and in situ cycloaddition to the 2-pyrone 2 to give 3 ( Science 2023 , 379 , 261. (organic-chemistry.org)
Palladium-Catalyzed, Multicomponent Approach to -Lactams via Aryl Halide Carbonylation. (tamu.edu)
Synthetic1
Synthetic efficiency raises the question of metal catalyzed cycloadditions to rings other than six-membered. (stanford.edu)
Readily1
N -Tosyl-3-halo-3-butenylamines underwent efficient Ullmann-type coupling to afford 2-alkylideneazetidines, which could be readily converted to the corresponding β-lactams by oxidation with O 3 . (organic-chemistry.org)
Efficient1
Efficient conversion of Schiff bases and carboxylic acids to β-lactams can be carried out at room temperature in CH 2 Cl 2 , using a cyanuric chloride- N,N -dimethyl formamide complex. (organic-chemistry.org)
Synthesis9
In order to ensure the correct stereochemistry (the phenyl group and the silyl ether must adopt a cis configuration) in the β-lactam a chiral auxiliary is used in the enolate synthesis. (wikipedia.org)
More importantly, the all-carbon [3 + 2] cycloaddition can forge vicinal all-carbon quaternary centers in a single step and has been demonstrated in the synthesis of complex natural products. (beilstein-journals.org)
In this review, we present the development of all-carbon [3 + 2] cycloadditions and illustrate their application in natural product synthesis reported in the last decade covering 2011-2020 (inclusive). (beilstein-journals.org)
These characteristics make the all-carbon [3 + 2] cycloaddition an appealing method and/or strategy in the synthesis of complex natural products ( Figure 2 ). (beilstein-journals.org)
A five-step total synthesis of (±)-aspidospermidine (1) based on a lactam strategy is reported. (elsevierpure.com)
Our synthesis features an iridium-catalyzed reductive Michael addition/[3+2] cycloaddition cascade to give a tricyclic ketone intermediate from a simple lactam via an azomethine ylide. (elsevierpure.com)
The developed strategy enables easily available lactams to be used as stable surrogates of multisubstituted amines and would be applicable to a unified total synthesis of complex Aspidospermaalkaloids. (elsevierpure.com)
He joined the lab of Thomas Lectka studying the reactions of chiral zwitterionic enolates for the enantioselective synthesis of beta-lactams and alpha-halogenated esters. (gatech.edu)
His work at Emory involved the synthesis of complex heterocyclic molecules via the Rh-catalyzed cyclization/cycloaddition of alpha-diazo carbonyl compounds. (gatech.edu)
Copper catalyzed azide-alkyne cycloaddition1
During the course of these investigations the copper catalyzed azide-alkyne cycloaddition has been used heavily for conjugation reactions involving small molecules and proteins. (umass.edu)
Staudinger1
3 ] The mechanism of the Staudinger cycloaddition and the rationale of the stereochemistry of the products has been investigated. (thieme.com)
Ojima2
The Ojima lactam is an organic compound of some importance in the commercial production of Taxol. (wikipedia.org)
This lactam was first synthesized by Iwao Ojima. (wikipedia.org)
Aldehydes1
Imines are most commonly prepared from aldehydes or ketones, and the imine nitrogen usually has an aromatic or aliphatic substituent that can easily be removed or altered after the formation of the β -lactam ring. (thieme.com)
Intermediate1
It is generally accepted that the ketene is attacked by the imine to form a zwitterionic intermediate which, upon conrotatory ring closure, forms the β -lactam ring. (thieme.com)
Centers1
More importantly, the all-carbon [3 + 2] cycloaddition can forge vicinal all-carbon quaternary centers [12] in a single-step operation and provides a direct access to various substituted five-membered carbocycles. (beilstein-journals.org)
Surrogate1
In fact, the proteolytic stable 1,4- or 4,1-disubstituted [1,2,3]triazolyl moiety is isosteric with the peptide bond and can function as a surrogate of the classical side chain-to-side chain lactam forming bridge. (unifi.it)
Method2
We have also shown that b- lactams are able discriminate between apo- and holo-ACPs and have used this difference in reactivity to develop a method of purifying holo-ACPs. (umass.edu)
1 ] This method is generally accepted as the most versatile and efficient route for the construction of the β -lactam skeleton. (thieme.com)
Mechanism1
Understanding the mechanism of direct visible-light-activated [2 + 2] cycloadditions mediated by Rh and Ir photocatalysts: combined computational and spectroscopic studies. (academictree.org)
Left1
The bicyclic carbon compound at the upper left is formed by a Diels-Alder cycloaddition of 1,4-benzoquinone with methyl trans-2,4-pentadienoate. (msu.edu)