Amido Esters Research Articles

ChemInform Abstract: Regioselective Preparation of 7‐Oxanorborna‐2,5‐diene‐2,3‐dicarboxylic Acid Derivatives by the Diels—Alder Reaction: A Selective Access to Furans by Retro‐Diels—Alder Reaction.

AbstractA convenient approach to furan derivatives is achieved through regioselective hydrolysis of Diels—Alder adducts (III), formation of diesters or amido esters, hydrogenation, and retro‐Diels—Alder reaction.

Unusual reaction of diazomethane with stereoisomeric 3-(benzylcarbamoyl)-5,6,7,8-tetrachloro-1,4-methano-1,2,3,4-tetrahydronaphthalene-2-carboxylic acids

Diazomethane is commonly used as efficient alkylating agent in the preparation of methyl esters and as a component in [2 + 3]-cycloaddition reactions [1]. However, there are no published data on dehydrating ability of diazomethane. With a view to accomplish cis–trans epimerization of cyclic amido acids I and II, an attempt was made to convert them into endo-cis and exo-cis amido esters III and IV by treatment with diazomethane in diethyl ether at 20°C. Unexpectedly, these reactions chemoselectively afforded the corresponding dicarboxylic acid imides V and VI, while even traces of esters III and IV were not detected. The structure of imides V and VI was confirmed by the H and C NMR spectra and independent synthesis from the corresponding anhydrides. It should be noted that known methods for the preparation of imides from amido acids require more severe conditions, in particular prolonged heating in high-boiling solvents (usually in DMF or Ac2O) in the presence of dehydrating agents [2]. rel-(1S,2R,3S,4R)-N-Benzyl-5,6,7,8-tetrachloro1,4-methano-1,2,3,4-tetrahydronaphthalen-2,3-dicarboximide (V). A solution of diazomethane in diethyl ether was added to a suspension of 0.9 g of amido acid I in diethyl ether until the mixture became homogeneous. The mixture was evaporated at 20oC, ISSN 1070-4280, Russian Journal of Organic Chemistry, 2013, Vol. 49, No. 10, pp. 1548–1549. © Pleiades Publishing, Ltd., 2013. Original Russian Text © S.A. Ismailov, 2013, published in Zhurnal Organicheskoi Khimii, 2013, Vol. 49, No. 10, pp. 1569–1570.

Regioselective Preparation of 7-Oxanorborna-2,5-diene-2,3-dicarboxylic Acid Derivatives by the Diels-Alder Reaction: A Selective Access to Furans by Retro-Diels-Alder Reaction

Hydrolysis of 1-substituted 7-oxanorborna-2,5-diene-2,3-dicarboxylates occurred regioselectively at the ester group in the 3-position to give monocarboxylic acids from which diesters containing two different alkoxy groups and amido esters were selectively prepared. Hydrogenation of these oxanorbornadiene derivatives followed by a retro-Diels–Alder reaction gave the corresponding furans as single regioisomers.

4-Hydroxy-1,1′-bis[(S)-1-phenylethyl]-5,5′,6,6′-tetrahydro-3,4′-bipyridine-2,2′(1H,1′H)-dione

The title bis-piperidine, C26H28N2O3, was unexpectedly obtained via a dimerization mechanism promoted by acetic acid when performing the Dieckmann cyclization of a chiral amido ester. The S,S configuration was assigned by reference to the enanti­omerically pure starting material. In the mol­ecule, two core heterocycles are linked by a σ bond. One ring includes a keto–enol group, while the other presents an enone functionality. Both rings present a conformation inter­mediate between envelope and screw-boat, and the dihedral angle between the mean planes passing through the rings [48.9 (1)°] is large enough to avoid hindrance between ring substituents. The enol tautomeric form in one ring favors the formation of strong inter­molecular O—H⋯O=C hydrogen bonds. The resulting one-dimensional supra­molecular structure features single-stranded helices running along the 21 screw axis parallel to [100].

ChemInform Abstract: Assignment of the Absolute Configuration of Polyfunctional Compounds by NMR Using Chiral Derivatizing Agents

AbstractReview: 154 refs.

Amido tyrosine esters: a promising new approach to antiviral nucleoside phosphonate prodrugs

Amido tyrosine esters: a promising new approach to antiviral nucleoside phosphonate prodrugs

An efficient and stereoselective synthesis of (3S,4R)-(−)-trans-4-(4′-fluorophenyl)-3-hydroxymethyl-N-methylpiperidine

An asymmetric conjugate addition reaction between a chiral α,β-unsaturated amido ester and ethyl-N-methylmalonamide has been used as a key step in the synthesis of (3S,4R)-(−)-trans-4-(4′-fluorophenyl)-3-hydroxymethyl-N-methylpiperidine, a key intermediate for (−)-paroxetine.

Selective Approach toward Multifunctionalized Lactams by Lewis Acid Promoted PhSe Group Transfer Radical Cyclization

We have developed a regiospecific and highly stereoselective strategy for constructing the five-/six-membered monocyclic and bicyclic nitrogen heterocycle skeletons using PhSe group transfer radical cyclization of alpha-phenylseleno amido esters promoted by a Lewis acid (e.g., Yb(OTf)(3)) under UV irradiation. We obtained 5-/6-exo-trig mode cyclization products for the N-allyl/homoallyl substrates, whereas the enamide substrate gave 5-endo-trig ring closure.

Highly stereoselective intramolecular α-arylation of self-stabilized non-racemic enolates: synthesis of α-quaternary α-amino acid derivatives

The 'one-pot' stereoselective conversion of N-(4-nitrobenzene)sulfonyl-alpha-amino acid tert-butyl esters into the corresponding N-alkyl-alpha-(4-nitrophenyl)-alpha-amino esters has been realized through N-alkylation of the starting amido esters, followed by N-C(alpha) migration of the p-nitrophenyl group and the loss of sulfur dioxide; the asymmetric induction is determined by an intermediate non-racemic enolate, without the need of an external source of chirality.

Mesogenic amido ester with cholesteryl moiety

A new series of mesogenic compounds having a cholesteryl moiety has been synthesized. Thirteen homologues were synthesized by condensing 4-(4′-n-alkoxy benzoyl) amido benzoyl chloride with cholesterol. The methyl to n-hexyl derivatives exhibit only cholesteric mesophases. The n-heptyl to n-dodecyl derivatives exhibit SC and cholesteric phases. The n-tetradecyl to n-octadecyl derivatives exhibit SC, SA and cholesteric phases. The plot of transition temperatures versus number of carbon atoms in the alkoxy chain exibit odd–even effect and falling tendency for cholesteric–isotropic transition temperatures. The mesomorphic and thermal stability is compared with other related homologous series. The results indicate that amide linkage enhances smectic as well as cholesteric thermal stability, but enhancement in smectic phase is much higher.

Prediction of the Lipophilicity of Some Plant Growth Stimulators by RP‐TLC and Relationship Between Slope and Intercept of TLC Equations

Using RP‐TLC with RP‐18 F254s and a methanol‐water mixture as the mobile phase, several new compounds (some plant growth stimulators, such as amido esters of ethanolamine and maleic and succinic acid derivatives) were studied. The log P values were calculated using fragmental constant or ACD/Labs Software database (Toronto, Canada). A good correlation was obtained between log P vs. R M0 and C 0, respectively. These relationships can be used for prediction of the lipophilicity of similar compounds from the same structural group. The relationship between intercepts and slopes from TLC equations showed a very good correlation. The results obtained by RP‐TLC demonstrated a basic feature of lipophilicity; that both series of compounds are two “congeneric” series.

Functional group-selective poisoning of molecular catalysts: a ruthenium cluster-catalysed highly amide-selective silane reduction that does not affect ketones or esters

The addition of amines eliminates the catalytic activity of a triruthenium cluster in the hydrosilane reduction of ketones and esters without affecting the rate of reduction of amides; selective reduction of the amide group in amido ketones and amido esters is accomplished.

Asymmetric synthesis of 1,4-amino alcohol ligands with a norbornene backbone for use in the asymmetric diethylzinc addition to benzaldehyde

The asymmetric synthesis of cis-1,4-amino alcohols with a norbornene backbone was performed starting with (2 S,3 R)-(−)- cis-hemiester 2 (98% ee). Chemoselective amination with NH 4OH and HMPTA followed by LAH reduction afforded 5 and 7, respectively. Amido ester 6 was transformed into chiral ligand 9 with Grignard reaction followed by LAH reduction. The chiral ligands 5, 7, and 9 were subjected to asymmetric diethylzinc addition to examine their effectiveness as chiral catalysts. Among these, chiral ligand 7 exhibited the highest enantioselectivity (88% ee).

Diastereoselective conjugate addition of organocuprates to chiral racemic olefinic amido esters. Formal total synthesis of paroxetine

Download options Please wait... Supplementary files Crystal structure data TXT (26K) Article information DOI https://doi.org/10.1039/B209181J Article type Paper Submitted 16 Sep 2002 Accepted 12 Nov 2002 First published 28 Jan 2003 Download Citation New J. Chem., 2003,27, 475-482 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Diastereoselective conjugate addition of organocuprates to chiral racemic olefinic amido esters. Formal total synthesis of paroxetine J. Cossy, O. Mirguet, D. G. Pardo and J. Desmurs, New J. Chem., 2003, 27, 475 DOI: 10.1039/B209181J To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Janine Cossy Olivier Mirguet Domingo Gomez Pardo Jean-Roger Desmurs

A short formal synthesis of paroxetine. Diastereoselective cuprate addition to a chiral racemic olefinic amido ester

A diastereoselective conjugate addition of an organocopper reagent to a chiral racemic olefinic amido ester has been used as the key step in a formal total synthesis of paroxetine.

ChemInform Abstract: Reactions of Fluoroalkanesulfonyl Azides with Carbocyclic β-Keto Esters: Structural Influence of Dicarbonyl Substrate on Distribution of Diazo and Ring-Contraction Products.

Abstract The diazo transfer reactions of fluoroalkanesulfonyl azides 1 with ethyl 2-oxocyclopentanecarboxylate 2, in the presence of triethylamine, give ring-opened diazo amido esters 3a–3d in high yields. Rhodium-catalyzed decompositions of these novel diazocarbonyl compounds 3 have been examined. The results show that β-hydride elimination by an intermediate carbene or rhodium-carbenoid is exclusively preferred, and the intramolecular cyclization onto the N-sulfonylcarbamoyl substituent does not take place. However, when fluoroalkanesulfonyl azides 1 react with ethyl 2-oxocyclohexanecarboxylate 5, the ring-contraction product cyclopentanecarboxylate 6 is formed as the only product.

Reactions of fluoroalkanesulfonyl azides with carbocyclic β-keto esters: structural influence of dicarbonyl substrate on distribution of diazo and ring-contraction products

The diazo transfer reactions of fluoroalkanesulfonyl azides 1 with ethyl 2-oxocyclopentanecarboxylate 2, in the presence of triethylamine, give ring-opened diazo amido esters 3a– 3d in high yields. Rhodium-catalyzed decompositions of these novel diazocarbonyl compounds 3 have been examined. The results show that β-hydride elimination by an intermediate carbene or rhodium-carbenoid is exclusively preferred, and the intramolecular cyclization onto the N-sulfonylcarbamoyl substituent does not take place. However, when fluoroalkanesulfonyl azides 1 react with ethyl 2-oxocyclohexanecarboxylate 5, the ring-contraction product cyclopentanecarboxylate 6 is formed as the only product.

A solid-phase approach towards the development of 3-aza-6,8-dioxabicyclo[3.2.1]octane scaffolds.

The development of new strategies for solid-phase synthesis of 3-aza-6,8-dioxabicyclo[3.2.1]octane scaffolds, named BTKa, is described. The preparation was made possible by the combination of three components: amines, alpha-halo-acetophenones, and sugar or tartaric acid derivatives. By anchoring each of the three components it was possible to synthesize BTKa compounds either as amino alcohols or amido esters. The compatibility of the protocols with different classes of amines and substituted alpha-halo-acetophenones was demonstrated.

Diazo transfer reactions of tosyl azide with carbocyclic β-keto esters: production and decomposition of ring-opened N-tosylcarbamoyl-substituted α-diazo esters

The diazo transfer reaction of tosyl azide 1 with methyl 2-oxocyclopentanecarboxylate 2a, ethyl 2-oxocyclohexanecarboxylate 2b and methyl 2-oxocycloheptanecarboxylate 2c, in the presence of triethylamine, gives ring-opened diazo amido esters 3a–c in fairly high yields. Similar reaction with ethyl 2-oxocyclooctanecarboxylate 2d and methyl camphor-3-carboxylate 2e also leads to the respective diazo esters 3d,e but accompanied by the corresponding azido transfer products 6, 7 to a significant (or major) extent. The thermal, photochemical and rhodium(II) acetate-catalysed decomposition of the novel diazocarbonyl compounds 3a–e has been examined. The results show that intramolecular cyclization onto the N-tosylcarbamoyl substituent can smoothly take place provided that it gives rise to a six-membered ring ylide or diazonium betaine intermediate. Otherwise, β-hydride elimination by an intermediate carbene or rhodium-carbenoid becomes the preferred, if not exclusive, decomposition mode. However, unusual behaviour is encountered with the diazo amido ester 3d in that its rhodium(II)-induced decomposition results in the preferential formation of the α-hydroxy ester 19.

The synthesis of lactam analogues of fentanyl

Fentanyl, sufentanil and alfentanil are clinically widely used anaesthetics and are structurally related to drugs with entirely different pharmacological activity such as droperidol, loperamide and lorcainide, etc. Therefore, in order to test their pharmacological activity, lactam analogues of fentanyl, a novel class of compounds, have been synthesized. In the first step, various primary amines have been selectively added to 1 equiv. of α,β-unsaturated esters, to afford the β-amino esters. N-Acylation of these intermediates with dimethyl malonate yields the amido esters, which have been further subjected to Dieckmann-type cyclization, to produce the corresponding 3-methoxycarbonylpiperidine-2,4-diones. The cyclization has been effected under phase-transfer conditions, utilizing potassium carbonate as base and 18-crown-6 as catalyst. This eliminates the need for strong and hazardous bases such as molten sodium or NaH. In the next step, acid hydrolysis and decarboxylation furnish the substituted piperidine-2,4-diones in good yields, as pure products. Alkylation of the N-phenethylpiperidine-2,4-dione with methyl iodide and potassium carbonate in DMSO gives the 3,3-dimethyl derivative. The alkylation procedure is also applicable to other alkylating agents. Reductive amination of the prepared piperidine-2,4-diones with aniline and NaBH3CN in buffered methanol gives the corresponding pure 4-anilino-2-piperidones. The lactam function can be readily reduced (NaBH4–BF3·Et2O), as exemplified with the 3,3-dimethyl derivative, thus providing access to additional fentanyl analogues, not readily accessible by other routes. The synthesis is completed by N-acylation of the anilines with propionyl chloride using triethylamine as base. The prepared 4-propionanilido-2-piperidones and 4-propionanilidopiperidines are expected to provide useful structure-activity relationship data in the pharmacological studies.