0000000000431633
AUTHOR
Melinda Nonn
A Selective Synthesis of Fluorinated Cispentacin Derivatives
A facile selective method has been developed for the synthesis of new fluorine-containing cispentacin stereoisomers. Mono- and difluorinated cispentacin derivatives were synthetized from a bicyclic β-lactam in five or six steps involving a regio- and stereoselective hydroxylation through iodooxazoline formation, followed by deoxygenation by fluorination. Starting from an enantiomerically pure bicyclic β-lactam obtained by enzymatic resolution of the racemic compound, an enantiodivergent procedure allowed the preparation of both dextro- and levorotatory difluorinated cispentacins.
A Stereocontrolled Protocol to Highly Functionalized Fluorinated Scaffolds through a Fluoride Opening of Oxiranes
A novel selective and substrate-dependent synthetic protocol has been developed towards the synthesis of various fluorine-containing, highly functionalized cycloalkane derivatives. The method involves the stereoselective epoxidation of some unsaturated cyclic beta-amino acid derivatives as model compounds, followed by a regioselective fluoride opening of oxiranes under various conditions with Deoxofluor and XtalFluor-E reagents, thereby offering an insight into this new epoxide opening methodology with fluoride.
Chemoselective, Substrate-directed Fluorination of Functionalized Cyclopentane β-Amino Acids
This work describes a substrate-directed fluorination of some highly functionalized cyclopentane derivatives. The cyclic products incorporating CH2 F or CHF2 moieties in their structure have been synthesized from diexo- or diendo-norbornene β-amino acids following a stereocontrolled strategy. The synthetic study was based on an oxidative transformation of the ring carbon-carbon double bond of the norbornene β-amino acids, followed by transformation of the resulted "all cis" and "trans" diformyl intermediates by fluorination with "chemodifferentiation".
Efficient regio- and stereoselective access to novel fluorinated ?-aminocyclohexanecarboxylates
A regio- and stereoselective method has been developed for the synthesis of novel fluorinated 2-aminocyclohexanecarboxylic acid derivatives with the fluorine attached to position 4 of the ring. The synthesis starts from either cis- or trans-β-aminocyclohex-4-enecarboxylic acids and involves regio- and stereoselective transformation of the ring C–C double bond through iodooxazine formation and hydroxylation, followed by hydroxy–fluorine or oxo–fluorine exchange.
Synthesis of Highly Functionalized Fluorinated Cispentacin Derivatives
Fluorinated highly functionalized cispentacin derivatives were synthetised starting from an unsaturated bicyclic b-lactam through C¼C bond functionalization via the dipolar cycloaddition of a nitrile oxide, isoxazoline opening, and fluorination by OH/F exchange.
Diversity-Oriented Synthesis of Highly Functionalized Alicycles across Dipolar Cycloaddition/Metathesis Reaction
AbstractThis Account gives an insight into the selective functionalization of some readily available commercial cyclodienes across simple chemical transformations into functionalized small-molecular scaffolds. The syntheses involved selective cycloadditions, followed by ring-opening metathesis (ROM) of the resulting azetidin-2-one derivatives or isoxazoline frameworks and selective cross metathesis (CM) by discrimination of the C=C bonds on the alkenylated heterocycles. The CM protocols have been described when investigated under various conditions with the purpose on exploring chemodifferentiation of the olefin bonds and a study on the access of the corresponding functionalized β-lactam or…
Fluorine-containing functionalized cyclopentene scaffolds through ring contraction and deoxofluorination of various substituted cyclohexenes
The fluorination of some highly‐functionalized cyclopentene derivatives, obtained from various substituted cyclohexenes through a ring‐opening/ring‐contraction procedure, has been investigated. The transformations were found to be highly substrate dependent, and led to the formation of various functionalized alicyclic compounds or heterocycles containing allyl difluoride or vinyl fluoride moieties. peerReviewed
An Insight into Substrate-Dependent Fluorination of some Highly Substituted Alicyclic Scaffolds
The substrate-dependent fluorination of some highly-functionalized cyclopentane derivatives with multiple chiral centers has been investigated. The key steps of the stereocontrolled syntheses are the oxidative cleavage of the ring carbon–carbon double bond of readily available diexo or diendo norbornene β-amino acid derivatives followed by transformation of the resulted dialdehyde stereoisomers by reduction. Finally, substrate-directable chemodifferentiation of different types of hydroxy groups under fluorination procedures gave various densely functionalized alicyclic derivatives or heterocycles.
Fluorination of some highly functionalized cycloalkanes: chemoselectivity and substrate dependence.
A study exploring the chemical behavior of some dihydroxylated β-amino ester stereo- and regioisomers, derived from unsaturated cyclic β-amino acids is described. The nucleophilic fluorinations involving hydroxy–fluorine exchange of some highly functionalized alicyclic diol derivatives have been carried out in view of selective fluorination, investigating substrate dependence, neighboring group assistance and chemodifferentiation.
Synthesis of novel fluorinated building blocks via halofluorination and related reactions.
A study exploring halofluorination and fluoroselenation of some cyclic olefins, such as diesters, imides, and lactams with varied functionalization patterns and different structural architectures is described. The synthetic methodologies were based on electrophilic activation through halonium ions of the ring olefin bonds, followed by nucleophilic fluorination with Deoxo-Fluor®. The fluorine-containing products thus obtained were subjected to elimination reactions, yielding various fluorine-containing small-molecular entities.
Asymmetric synthesis of chloroisothreonine derivatives via syn-stereoselective Mannich-type additions across N-sulfinyl-α- chloroimines
Mannich-type reactions of O-Boc glycolic esters across chiral N-sulfinyl-α-chloroaldimines resulted in the efficient and syn-stereoselective synthesis of new γ-chloro-α-hydroxy-β-amino esters (dr > 99:1). The α-coordinating ability of the chlorine atom was of great importance for the diastereoselectivity of the Mannich-type reaction and overruled the chelation of the sulfinyl oxygen with the lithium ion of the incoming E-enolate in the transition state model. These novel chloroisothreonine derivatives proved to be excellent building blocks in asymmetric synthesis of novel syn-β,γ-aziridino-α-hydroxy esters and biologically relevant trans-oxazolidinone carboxylic esters.
Back Cover: Chemoselective, Substrate-directed Fluorination of Functionalized Cyclopentane β-Amino Acids (Chem. Asian J. 23/2016)
Chemodiscrimination of Olefin Bonds Through Cross‐Metathesis Reactions – Synthesis of Functionalized β‐Lactam and β‐Amino Acid Derivatives
Synthesis of highly functionalized β-aminocyclopentanecarboxylate stereoisomers by reductive ring opening reaction of isoxazolines
A rapid and simple procedure was devised for the synthesis of multifunctionalized cyclic β-amino esters and γ-amino alcohols via the 1,3-dipolar cycloaddition of nitrile oxides to β-aminocyclopentenecarboxylates. The opening of the isoxazoline reductive ring to the corresponding highly functionalized 2-aminocyclopentanecarboxylates occurred stereoselectively with good yields.
Fluorine-Containing Functionalized Cyclopentene Scaffolds Through Ring Contraction and Deoxofluorination of Various Substituted Cyclohexenes
An insight into the synthesis of novel aryl-substituted alicyclic β-amino acid derivatives through substrate-directed palladium-catalysed regio- and stereoselective cross-coupling
Novel aryl-substituted alicyclic β-amino acid derivatives were synthesized through substrate-determined palladium-catalysed cross-coupling of aryl iodides with five- or six-membered cycloalkene β-amino esters. The arylations were investigated with different catalysts, solvents, bases and aryl halides, and with some cyclohexene 2-aminocarboxylate isomers. The stereochemistry and the position of the ring olefinic bond of the starting 2-aminocycloalkanecarboxylate influenced the coupling reaction, and predetermined the structure of the arylated product.
Diversity-Oriented Stereocontrolled Synthesis of Some Piperidine- and Azepane-Based Fluorine-Containing β-Amino Acid Derivatives
AbstractStructural diversity-oriented synthesis of some azaheterocyclic β-amino acid derivatives has been accomplished by selective functionalization of readily available cyclodienes. The stereocontrolled synthetic concept was based on the oxidative ring cleavage of unsaturated cyclic β-amino acids derived from cycloalkadiene, followed by ring closing with double reductive amination, which furnished some conformationally restricted β-amino acid derivatives with a piperidine or azepane core.
Synthesis of novel isoxazoline-fused cispentacin stereoisomers
Abstract New isoxazoline-fused cispentacins were prepared by the 1,3-dipolar cycloaddition of nitrile oxides to β-amino esters containing a cyclopentene skeleton. This synthetic procedure gave regio- and diastereoisomers of the cispentacins. The synthetic route was extended to the synthesis of these compounds in enantiomerically pure form.
Selective nitrile oxide dipolar cycloaddition for the synthesis of highly functionalized β-aminocyclohexanecarboxylate stereoisomers
Highly functionalized β-aminocyclohexanecarboxylate regio- and stereoisomers were synthesized from a bicyclic β-lactam by successive regioselective iodolactonization, stereo- and regioselective nitrile oxide cycloaddition, lactone ring-opening and isoxazoline ring-opening.
A novel and selective fluoride opening of aziridines by XtalFluor-E. synthesis of fluorinated diamino acid derivatives.
The selective introduction of fluorine onto the skeleton of an aminocyclopentane or cyclohexane carboxylate has been developed through a novel and efficient fluoride opening of an activated aziridine ring with XtalFluor-E. The reaction proceeded through a stereoselective aziridination of the olefinic bond of a bicyclic lactam and regioselective aziridine ring opening with difluorosulfiliminium tetrafluoroborate with the neighboring group assistance of the sulfonamide moiety to yield fluorinated diamino acid derivatives. The method based on the selective aziridine opening by fluoride has been generalized to afford access to mono- or bicyclic fluorinated substances.
Synthesis of fluorinated amino acid derivatives through late-stage deoxyfluorinations
Abstract Fluorine chemistry has represented a hot topic in drug research over the last decade. Because of their pharmaceutical potential, fluorine-containing amino acids and related derivatives have acquired high importance among medicinal chemists. Therefore their synthesis and the development of various synthetic methods for these types of molecular scaffolds have gained increasing interest in synthetic organic chemistry. The current review focuses on synthetic protocols towards fluorine-containing amino acid derivatives through late-stage fluorination with various nucleophilic reagents, describing the access of various open-chain and cyclic α-, β-, γ-amino acid derivatives.
Synthesis of densely functionalized cispentacin derivatives through selective aziridination and aziridine opening reactions: Orthogonally protected di- and triaminocyclopentanecarboxylates
A novel substrate-directed synthetic route to a series of highly functionalized, orthogonally protected di- or triaminocyclopentanecarboxylate derivatives with multiple chiral centres from an unsaturated bicyclic β-lactam has been accomplished by applying stereoselective ring C–C double bond aziridination with chloramine-T and phenyltrimethylammonium tribromide, followed by regioselective aziridine opening with different N,O nucleophiles and hydrides. The functionalization strategy was successfully extended for access to enantiomerically pure orthogonally protected triaminocarboxylates.
Substrate-dependent fluorinations of highly functionalized cycloalkanes
Abstract Substrate-dependent fluorinations of several highly functionalized cycloalkanes with multiple stereocentres were investigated. The synthetic transformations were based on selective functionalization of the ring C C bonds of the readily available bicyclic β-lactams by epoxidation and regioselective nucleophilic oxirane opening with azide or cyanide, followed by hydroxy–fluorine exchange with Deoxofluor. Depending on the substituents and their relative steric arrangement, the attempted fluorinations produced different types of substituted cycloalkanes. These selective, substrate-directed synthetic procedures and their presumed pathways towards interesting highly functionalized fluori…
Asymmetric Methods for Carbon‐Fluorine Bond Formation
Ring-opening metathesis of some strained bicyclic systems; stereocontrolled access to diolefinated saturated heterocycles with multiple stereogenic centers
Ring-opening metathesis (ROM) of various unsaturated, constrained bicyclic ring systems has been investigated with the use of commercial ruthenium-based catalysts. Starting from various cyclodienes, the corresponding derived bicyclic lactone, lactam, and isoxazoline derivatives were submitted to ROM under ethenolysis. These functionalized, strained bicyclic systems afforded novel highly-functionalized diolefinated heterocyclic scaffolds in ROM reactions with stereocontrol, through the conservation of the configuration of the stereogenic centers of the starting compounds.
CCDC 1495998: Experimental Crystal Structure Determination
Related Article: Loránd Kiss, Melinda Nonn, Reijo Sillanpää, Matti Haukka, Santos Fustero, Ferenc Fülöp|2016|Chem.Asian J.|11|3376|doi:10.1002/asia.201601046
CCDC 914060: Experimental Crystal Structure Determination
Related Article: Lorand Kiss, Melinda Nonn, Reijo Sillanpaa, Santos Fustero, Ferenc Fulop|2013|Beilstein J.Org.Chem.|9|1164|doi:10.3762/bjoc.9.130
CCDC 977961: Experimental Crystal Structure Determination
Related Article: Gert Callebaut, Filip Colpaert, Melinda Nonn, Loránd Kiss, Reijo Sillanpää, Karl W. Törnroos, Ferenc Fülöp, Norbert De Kimpe, Sven Mangelinckx|2014|Org.Biomol.Chem.|12|3393|doi:10.1039/C4OB00243A
CCDC 1562225: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Melinda Nonn, Santos Fustero, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2017|Beilstein J.Org.Chem.|13|2364|doi:10.3762/bjoc.13.233
CCDC 1814087: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Melinda Nonn, Santos Fustero, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2018|Eur.J.Org.Chem.|2018|3735|doi:10.1002/ejoc.201800057
CCDC 1057565: Experimental Crystal Structure Determination
Related Article: Melinda Nonn, Loránd Kiss, Matti Haukka, Santos Fustero, Ferenc Fülöp|2015|Org.Lett.|17|1074|doi:10.1021/acs.orglett.5b00182
CCDC 2011188: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Tamás T Novák, Melinda Nonn, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2020|Beilstein J.Org.Chem.|16|2562|doi:10.3762/bjoc.16.208
CCDC 1401005: Experimental Crystal Structure Determination
Related Article: Loránd Kiss, Attila Márió Remete, Melinda Nonn, Santos Fustero, Reijo Sillanpää, Ferenc Fülöp|2016|Tetrahedron|72|781|doi:10.1016/j.tet.2015.12.017
CCDC 1038709: Experimental Crystal Structure Determination
Related Article: Melinda Nonn, Loránd Kiss, Mikko M. Hänninen, Ferenc Fülöp|2015|RSC Advances|5|13628|doi:10.1039/C4RA16196C
CCDC 977962: Experimental Crystal Structure Determination
Related Article: Gert Callebaut, Filip Colpaert, Melinda Nonn, Loránd Kiss, Reijo Sillanpää, Karl W. Törnroos, Ferenc Fülöp, Norbert De Kimpe, Sven Mangelinckx|2014|Org.Biomol.Chem.|12|3393|doi:10.1039/C4OB00243A
CCDC 2011187: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Tamás T Novák, Melinda Nonn, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2020|Beilstein J.Org.Chem.|16|2562|doi:10.3762/bjoc.16.208
CCDC 1495999: Experimental Crystal Structure Determination
Related Article: Loránd Kiss, Melinda Nonn, Reijo Sillanpää, Matti Haukka, Santos Fustero, Ferenc Fülöp|2016|Chem.Asian J.|11|3376|doi:10.1002/asia.201601046
CCDC 914059: Experimental Crystal Structure Determination
Related Article: Lorand Kiss, Melinda Nonn, Reijo Sillanpaa, Santos Fustero, Ferenc Fulop|2013|Beilstein J.Org.Chem.|9|1164|doi:10.3762/bjoc.9.130
CCDC 2011186: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Tamás T Novák, Melinda Nonn, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2020|Beilstein J.Org.Chem.|16|2562|doi:10.3762/bjoc.16.208
CCDC 982910: Experimental Crystal Structure Determination
Related Article: Loránd Kiss, Melinda Nonn, Enikő Forró, Reijo Sillanpää, Santos Fustero, Ferenc Fülöp|2014|Eur.J.Org.Chem.|2014|4070|doi:10.1002/ejoc.201402121
CCDC 977960: Experimental Crystal Structure Determination
Related Article: Gert Callebaut, Filip Colpaert, Melinda Nonn, Loránd Kiss, Reijo Sillanpää, Karl W. Törnroos, Ferenc Fülöp, Norbert De Kimpe, Sven Mangelinckx|2014|Org.Biomol.Chem.|12|3393|doi:10.1039/C4OB00243A
CCDC 1814088: Experimental Crystal Structure Determination
Related Article: Attila Márió Remete, Melinda Nonn, Santos Fustero, Matti Haukka, Ferenc Fülöp, Loránd Kiss|2018|Eur.J.Org.Chem.|2018|3735|doi:10.1002/ejoc.201800057
CCDC 914062: Experimental Crystal Structure Determination
Related Article: Lorand Kiss, Melinda Nonn, Reijo Sillanpaa, Santos Fustero, Ferenc Fulop|2013|Beilstein J.Org.Chem.|9|1164|doi:10.3762/bjoc.9.130
CCDC 982909: Experimental Crystal Structure Determination
Related Article: Loránd Kiss, Melinda Nonn, Enikő Forró, Reijo Sillanpää, Santos Fustero, Ferenc Fülöp|2014|Eur.J.Org.Chem.|2014|4070|doi:10.1002/ejoc.201402121
CCDC 914061: Experimental Crystal Structure Determination
Related Article: Lorand Kiss, Melinda Nonn, Reijo Sillanpaa, Santos Fustero, Ferenc Fulop|2013|Beilstein J.Org.Chem.|9|1164|doi:10.3762/bjoc.9.130
CCDC 1008231: Experimental Crystal Structure Determination
Related Article: Melinda Nonn, Loránd Kiss, Enikő Forró, Reijo Sillanpää, Ferenc Fülöp|2014|Tetrahedron|70|8511|doi:10.1016/j.tet.2014.09.071
CCDC 1057564: Experimental Crystal Structure Determination
Related Article: Melinda Nonn, Loránd Kiss, Matti Haukka, Santos Fustero, Ferenc Fülöp|2015|Org.Lett.|17|1074|doi:10.1021/acs.orglett.5b00182