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18. N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

Author

Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Mendes, Joseane A., Costa, Paulo R.R., Yus, Miguel, Foubelo, Francisco, Buarque, Camilla D., Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Mendes, Joseane A., Costa, Paulo R.R., Yus, Miguel, Foubelo, Francisco, and Buarque, Camilla D.

Abstract

The synthesis of nitrogen-containing heterocycles, including natural alkaloids and other compounds presenting different types of biological activities have proved to be successful employing chiral sulfinyl imines derived from tert-butanesulfinamide. These imines are versatile chiral auxiliaries and have been extensively used as eletrophiles in a wide range of reactions. The electron-withdrawing sulfinyl group facilitates the nucleophilic addition of organometallic compounds to the iminic carbon with high diastereoisomeric excess and the free amines obtained after an easy removal of the tert-butanesulfinyl group can be transformed into enantioenriched nitrogen-containing heterocycles. The goal of this review is to the highlight enantioselective syntheses of heterocycles involving the use of chiral N-tert-butanesulfinyl imines as reaction intermediates, including the synthesis of several natural products. The synthesis of nitrogen-containing heterocycles in which the nitrogen atom is not provided by the chiral imine will not be considered in this review. The sections are organized according to the size of the heterocycles. The present work will comprehensively cover the most pertinent contributions to this research area from 2012 to 2020. We regret in advance that some contributions are excluded in order to maintain a concise format.

Published
2021

29. Syn-selective Michael addition of nitromethane derivatives to enoates derived from (R)-(+)-glyceraldehyde acetonide

Author

Costa, Jeronimo S., Dias, Ayres G., Anholeto, Aline L., Monteiro, Monica D., Patrocinio, Vera L., and Costa, Paulo R.R.

Subjects
Methane -- Analysis, Organic compounds -- Synthesis, Carbonyl compounds -- Research, Biological sciences, Chemistry
Abstract

A series of cis-3,4-disubstituted gamma-butyrolactones was synthesized by the syn-selective Michael addition of primary and secondary nitromethane derivatives to chiral enoates in the presence of TBAF.3H2O or DBU. The synthetic process was characterized by the removal of the nitro group in the syn adducts via the reduction of the C-N bonds. Furthermore, the low diastereoselectivity of the additions of secondary nitromethane derivatives indicated the similar energy levels of the transition states.

Published
1997

30. Switching Diastereoselectivity in Catalytic Enantioselective (3+2) Cycloadditions of Azomethine Ylides Promoted by Metal Salts and Privileged Segphos-Derived Ligands

Author

Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Caleffi, Guilherme S., Larrañaga Agirre, Olatz, Ferrándiz-Saperas, Marcos, Costa, Paulo R.R., Nájera, Carmen, Cózar Ruano, Abel de, Cossío Mora, Fernando Pedro, Sansano, Jose M., Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Caleffi, Guilherme S., Larrañaga Agirre, Olatz, Ferrándiz-Saperas, Marcos, Costa, Paulo R.R., Nájera, Carmen, Cózar Ruano, Abel de, Cossío Mora, Fernando Pedro, and Sansano, Jose M.

Abstract

Catalytic enantioselective 1,3-dipolar cycloaddition between imino esters and electrophilic alkenes, employing chiral metal complexes derived from copper(I) and silver(I) salts and (S)-DM- or (S)-DTBM-Segphos as ligands produces diastereodivergently exo- or endo-cycloadducts, respectively. The effect of the functional group of the dipolarophile and the fine tuning of the catalyst plays an important role in promoting reverse diastereoselectivities. The origins of experimentally observed enantioselectivity and diastereoselectivity data, as well as the origin of the observed switched endo/exo ratios, are also explained by means of density functional theory calculations.

Published
2019

31. Enantioselective Synthesis, DFT Calculations, and Preliminary Antineoplastic Activity of Dibenzo 1-Azaspiro[4.5]decanes on Drug-Resistant Leukemias

Author

Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Mendes, Joseane A., Merino, Pedro, Soler, Tatiana, Salustiano, Eduardo J., Costa, Paulo R.R., Yus, Miguel, Foubelo, Francisco, Buarque, Camilla D., Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Mendes, Joseane A., Merino, Pedro, Soler, Tatiana, Salustiano, Eduardo J., Costa, Paulo R.R., Yus, Miguel, Foubelo, Francisco, and Buarque, Camilla D.

Abstract

The addition of 2-bromobenzylmagnesium bromide to chiral N-tert-butanesulfinyl imines derived from tetralone-type ketones proceeds with high levels of diastereocontrol. The resulting sulfinamide derivatives were transformed into dibenzoazaspiro compounds after a palladium-catalyzed intramolecular N-arylation. DFT calculations have been performed to rationalize the stereochemical course of the reaction. Similar results have been obtained considering either diethyl ether or toluene as a solvent, in both cases in an excellent agreement with experimental findings. NCI topological calculations have also been used to evidence crucial noncovalent interactions. In addition, the azaspiro compounds reduced the viability of chronic myeloid leukemia cells in the micromolar range. Notably, both the halogen-substituted (R)- and (S)-8g and -8h as well as (R)-8j were at least two times more effective on a multidrug-resistant derivative than on the parental cell line, exerting a collateral sensitivity effect.

Published
2019

43. Palladium-catalyzed tandem Heck-lactonization from o-iodophenols and enoates: synthesis of coumarins and the study of the mechanism by electrospray ionization mass spectrometry

Author

de A. Fernandes, Talita, Vaz, Boniek Gontijo, Eberlin, Marcos N., da Silva, Alcides J.M., and Costa, Paulo R.R.

Subjects
Ionization -- Analysis, Lactones -- Chemical properties, Mass spectrometry -- Usage, Palladium catalysts -- Chemical properties, Phenols -- Structure, Phenols -- Chemical properties, Biological sciences, Chemistry
Abstract

The tandem Heck-lactonization reaction between enoates and o-iodophenols is analyzed in the presence of substoichiometric amounts of Pd[(OAc).sub.2] or Pd[Cl.sub.2], leading to coumarins. Electrospray ionization is used for transferring ions directly from solution to the gas phase, and mass spectrometry for structural assignments, key cationic palladium intermediates are intercepted and structurally characterized for this type of reaction.

Published
2010

46. Stereoselective conjugate addition of benzyle phenylsulfonyl carbanions to enoates derived from D-mannitol

Author

Ferreira, Andre R.G., de A. Vilela, Guilherme V.M., Amorim, Mauro B., Perry, Katia P., da Silva, Antonio J.R., Dias, Ayres G., and Costa, Paulo R.R.

Subjects
Mannitol -- Properties, Mannitol -- Analysis, Carbon compounds -- Properties, Carbon compounds -- Analysis, Nucleophiles -- Analysis, Biological sciences, Chemistry
Abstract

Conjugate addition is a versatile reaction that allows the formation of new carbon-carbon or carbon-heteroatom bonds from a variety of acceptors and nucleophiles. The stereochemical outcome of the conjugate additions to enoates is shown to be dependent on the nature of the nucleophiles.

Published
2004

47. Synthesis of Chromen[4,3-b]pyrrolidines by Intramolecular 1,3-Dipolar Cycloadditions of Azomethine Ylides: An Experimental and Computational Assessment of the Origin of Stereocontrol

Author

Costa, Paulo R.R., Sansano, Jose M., Cossío, Unai, Barcellos, Julio C.F., Dias, Ayres G., Nájera, Carmen, Arrieta, Ana, Cózar Ruano, Abel de, Cossío Mora, Fernando Pedro, Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, and Síntesis Asimétrica (SINTAS)

Subjects
Kinetics, Química Orgánica, Reaction mechanisms, Azomethine ylides, Transition states, Cycloaddition
Abstract

Azomethine ylides, generated from imine-derived O-cinnamyl or O-crotonyl salicylaldeyde and α-amino acids, undergo intramolecular 1,3-dipolar cycloaddition, leading to chromene[4,3-b]pyrrolidines. Two reaction conditions are used: (a) microwave-assisted heating (200 W, 185 °C) of a neat mixture of reagents, and (b) conventional heating (170 °C) in PEG-400 as solvent. In both cases, a mixture of two epimers at the α-position of the nitrogen atom in the pyrrolidine nucleus was formed through the less energetic endo-approach (B/C ring fusion). In many cases, the formation of the stereoisomer bearing a trans-arrangement into the B/C ring fusion was observed in high proportions. Comprehensive computational and kinetic simulation studies are detailed. An analysis of the stability of transient 1,3-dipoles, followed by an assessment of the intramolecular pathways and kinetics are also reported. Financial support was provided by the Brasilian Universiade Federal do Rio de Janeiro (UFRJ), the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), by the Spanish Ministerio de Ciencia e Innovación (MICINN) (projects CTQ2010-20387, Consolider Ingenio 2010, CSD2007-00006), the Spanish Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P, CTQ2014-51912-REDC, and CTQ2013-45415-P), the Fondos Europeos para el Desarrollo Regional (FEDER), the Generalitat Valenciana (PROMETEO 2009/039 and PROMETEOII/2014/017), the Basque Government (GV/EJ, grant IT-324-07), and the Universities of Alicante and of the Basque Country (UPV/EHU) (UFI11/22 QOSYC).

Published
2015

48. Synthesis of 5-Carbapterocarpens by α-Arylation of Tetralones Followed by One-Pot Demethylation/Cyclization with BBr3

Author

Fernandes, Talita de A., Domingos, Jorge L.O., Rocha, Luiza I.A. da, Medeiros, Sabrina de, Nájera, Carmen, Costa, Paulo R.R., Universidad de Alicante. Departamento de Química Orgánica, and Síntesis Asimétrica (SINTAS)

Subjects
Química Orgánica, Oxygen heterocycles, Cyclization, C–C coupling, Medicinal chemistry, Arylation, Pterocarpens
Abstract

5-Carbapterocarpens, one of them displaying estrogenic activity, were prepared from α-aryltetralones in high yields through a one-pot, BBr3-promoted O-demethylation and cyclization sequence. The key α-aryltetralone intermediates were obtained by direct α-arylation of tetralones with o-alkoxybromoarenes in the presence of Pd2(dba)3 (2.5 mol-%) and tBu3PHBF4 (10 mol-%) as catalysts, together with 2.5 equiv. of KOH in dioxane/H2O (4:1), under microwave irradiation conditions (80 W, 100 °C, 40 min), leading to α-monoaryltetralones in good yields. Financial support from the Brazilian agencies Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES-DGU Project number 200/09), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) is gratefully acknowledged. The Spanish Ministerio de Ciencia e Innovación (MICINN) (project numbers PHB2008-0037-PC, CTQ2007-62771/BQU, CTQ2010-20387, Consolider INGENIO 2010 grant number CSD2007-00006), (FEDER), Generalitat Valenciana (project PROMETEO/2009/038), and the University of Alicante are also gratefully acknowledged.

Published
2014

50. Ligand-Free Palladium-Catalyzed Oxyarylation of Dihydronaphthal­enes and Chromenequinone with o-Iodophenols and 3-Iodolawsone in PEG-400: An Efficient Synthesis of 5-Carbapterocarpans and Pterocarpanquinones

Author

Universidad de Alicante. Departamento de Química Orgánica, Moraes, Paula de Freitas de, Gaspar, Francisco V., Borges, Rackel H.F., Netto, Chaquip D., Leão, Raquel A.C., Nájera, Carmen, Costa, Paulo R.R., Universidad de Alicante. Departamento de Química Orgánica, Moraes, Paula de Freitas de, Gaspar, Francisco V., Borges, Rackel H.F., Netto, Chaquip D., Leão, Raquel A.C., Nájera, Carmen, and Costa, Paulo R.R.

Abstract

Dihydronaphthalenes were oxyarylated with o-iodophenols, in PEG-400 at 140 or 170 °C, leading regio- and stereoselectively to 5-carbapterocarpans. By using Pd(OAc)2 (5–10 mol%) as precatalyst and Ag2CO3 (1.1 equiv) as base (conditions A), products were obtained in good to excellent chemical yields, in 5–30 minutes, irrespective of the pattern of substitution the starting materials. Alternatively, when p-hydroxyacetophenone oxime derived palladacycle (1 mol%) was used as precatalyst, and dicyclohexylamine (2 equiv) was used as base (silver-free, conditions B), the corresponding adducts were obtained in moderate to good yields, in 0.5 to 4 hours. Finally, the oxyarylation of dihydronaphthalenes­ and chromenquinone with o-iodophenols and 3-iodolawsone in PEG-400 under conditions A led regio- and stereoselectively to the formation of carbapterocarpanquinones and pterocarpanquinones in moderate yield.

Published
2015

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