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Alejandra G Suarez - One of the best experts on this subject based on the ideXlab platform.
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Tuning zirconia-supported metal catalysts for selective one-step hydrogenation of Levoglucosenone
Green Chemistry, 2019Co-Authors: Jaime Mazarío, Alejandra G Suarez, Rolando A. Spanevello, Miriam Parreño Romero, Patricia Concepción, Marvin Chávez-sifontes, María B. Comba, Marcelo Eduardo DomineAbstract:Levoglucosenone, directly produced from cellulose-containing residual biomass via pyrolysis treatments, is believed to be a promising bio-renewable platform for both fine and commodity chemicals. In this work, the possibilities given by tuneable catalysts based on Pd and Pt supported on metallic oxides to produce the desired product in the one-pot hydrogenation of Levoglucosenone are evaluated. Particularly, the excellent catalytic performance of Pd/ZrO2 and Pt/ZrO2 type materials for the synthesis of dihydroLevoglucosenone (or Cyrene) and levoglucosanol, respectively, during the mild hydrogenation of Levoglucosenone is demonstrated. In the Cyrene synthesis, the Pd/t-ZrO2 material showed the best catalytic activity compared to other Pd-supported on metallic oxides. This catalyst achieved nearly 95% yields of Cyrene by working under mild reaction conditions, with very low catalyst loadings (≈3 wt%) and using water as the solvent. On the other hand, the one-pot hydrogenation of Levoglucosenone to levoglucosanol is reported for the first time with a Pt-based heterogeneous catalyst (Pt/ZrO2-mix, yield ≈90%), by working at low temperatures and mild H2 pressures with water as the solvent. Comparison of the results attained with other Pt-supported metallic oxides let us to conclude that the metal crystal facets (specifically the 100 facet) play an important role in the hydrogenation process to give levoglucosanol selectively. In addition, the stability and re-usability of both catalysts under operational conditions are also evaluated. Finally, catalytic tests including the use of crude bio-liquids obtained from cellulose-rich biomass pyrolysis and containing ≈66 wt% of Levoglucosenone are also assayed, thus demonstrating the possibility of scaling-up the process over these metals supported on zirconia catalysts.
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Synthesis of new chiral 1,3-aminoalcohols derived from Levoglucosenone and their application in asymmetric alkylations
Tetrahedron Letters, 2015Co-Authors: María Marta Zanardi, Alejandra G SuarezAbstract:We have developed a simple procedure for the preparation of chiral 1,3-aminoalcohols using the biomass derivative Levoglucosenone, as the chiral starting material. 1,3-aminoalcohols, bearing primary and tertiary amino groups, were tested as chiral catalysts in the asymmetric addition of diethyl zinc to benzaldehyde.
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New chiral 1,2-aminoalcohols derived from biomass and their application in diethyl zinc additions
Tetrahedron Letters, 2014Co-Authors: María Marta Zanardi, María Celeste Botta, Alejandra G SuarezAbstract:A convenient procedure for the preparation of chiral 1,2-aminoalcohols starting from Levoglucosenone, a biomass derivative, is described. The 1,2-aminoalcohols, bearing primary, secondary, and tertiary amino groups, were tested as chiral catalysts in the asymmetric addition of diethyl zinc to benzaldehyde.
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Synthesis of tri-O-acetyl-D-allal from Levoglucosenone.
Organic letters, 2012Co-Authors: Enrique D. V. Giordano, Alejandra G Suarez, Agustina Frinchaboy, Rolando A. SpanevelloAbstract:Tri-O-acetyl-d-allal has been enantiospecifically synthesized in six steps from Levoglucosenone in 55% overall yield. A key step in the synthesis is the anhydro bridge ring-opening with concomitant formation of a 1,3-oxathiolane-2-thione ring.
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dft calculations induced a regiochemical outcome revision of the diels alder reaction between Levoglucosenone and isoprene
Tetrahedron Letters, 2011Co-Authors: Ariel M. Sarotti, Alejandra G Suarez, Rolando A. SpanevelloAbstract:Abstract An appealing inversion in the regiochemical outcome of Diels–Alder reactions between Levoglucosenone ( 1 ) and its α-bromo derivative ( 5 ) with isoprene ( 2 ) was studied computationally. Based on different DFT calculations we concluded that both reactions should display the same regioselectivity. This result was further validated experimentally.
Rolando A. Spanevello - One of the best experts on this subject based on the ideXlab platform.
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Tuning zirconia-supported metal catalysts for selective one-step hydrogenation of Levoglucosenone
Green Chemistry, 2019Co-Authors: Jaime Mazarío, Alejandra G Suarez, Rolando A. Spanevello, Miriam Parreño Romero, Patricia Concepción, Marvin Chávez-sifontes, María B. Comba, Marcelo Eduardo DomineAbstract:Levoglucosenone, directly produced from cellulose-containing residual biomass via pyrolysis treatments, is believed to be a promising bio-renewable platform for both fine and commodity chemicals. In this work, the possibilities given by tuneable catalysts based on Pd and Pt supported on metallic oxides to produce the desired product in the one-pot hydrogenation of Levoglucosenone are evaluated. Particularly, the excellent catalytic performance of Pd/ZrO2 and Pt/ZrO2 type materials for the synthesis of dihydroLevoglucosenone (or Cyrene) and levoglucosanol, respectively, during the mild hydrogenation of Levoglucosenone is demonstrated. In the Cyrene synthesis, the Pd/t-ZrO2 material showed the best catalytic activity compared to other Pd-supported on metallic oxides. This catalyst achieved nearly 95% yields of Cyrene by working under mild reaction conditions, with very low catalyst loadings (≈3 wt%) and using water as the solvent. On the other hand, the one-pot hydrogenation of Levoglucosenone to levoglucosanol is reported for the first time with a Pt-based heterogeneous catalyst (Pt/ZrO2-mix, yield ≈90%), by working at low temperatures and mild H2 pressures with water as the solvent. Comparison of the results attained with other Pt-supported metallic oxides let us to conclude that the metal crystal facets (specifically the 100 facet) play an important role in the hydrogenation process to give levoglucosanol selectively. In addition, the stability and re-usability of both catalysts under operational conditions are also evaluated. Finally, catalytic tests including the use of crude bio-liquids obtained from cellulose-rich biomass pyrolysis and containing ≈66 wt% of Levoglucosenone are also assayed, thus demonstrating the possibility of scaling-up the process over these metals supported on zirconia catalysts.
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Cytotoxic effect of Levoglucosenone and related derivatives against human hepatocarcinoma cell lines.
Bioorganic & medicinal chemistry letters, 2016Co-Authors: Germán F. Giri, Mauro Danielli, Raúl A. Marinelli, Rolando A. SpanevelloAbstract:Levoglucosenone has been used as template for the synthesis of a wide variety of compounds with an impressive structural variability. However, scarce work has been done regarding the generation of new bioactive entities. Here we report the cytotoxic effect of Levoglucosenone and some related derivatives against hepatocarcinoma cell lines. Compounds were obtained in only one synthetic step and one of them showed an activity within the range of IC50 values of cisplatin, a frequently administered chemotherapy drug.
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Synthesis of Tri‑O‑acetyl‑d‑allal from Levoglucosenone
2016Co-Authors: Enrique D. V. Giordano, Agustina Frinchaboy, Alejandra G. Suárez, Rolando A. SpanevelloAbstract:Tri-O-acetyl-d-allal has been enantiospecifically synthesized in six steps from Levoglucosenone in 55% overall yield. A key step in the synthesis is the anhydro bridge ring-opening with concomitant formation of a 1,3-oxathiolane-2-thione ring
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Synthesis of tri-O-acetyl-D-allal from Levoglucosenone.
Organic letters, 2012Co-Authors: Enrique D. V. Giordano, Alejandra G Suarez, Agustina Frinchaboy, Rolando A. SpanevelloAbstract:Tri-O-acetyl-d-allal has been enantiospecifically synthesized in six steps from Levoglucosenone in 55% overall yield. A key step in the synthesis is the anhydro bridge ring-opening with concomitant formation of a 1,3-oxathiolane-2-thione ring.
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dft calculations induced a regiochemical outcome revision of the diels alder reaction between Levoglucosenone and isoprene
Tetrahedron Letters, 2011Co-Authors: Ariel M. Sarotti, Alejandra G Suarez, Rolando A. SpanevelloAbstract:Abstract An appealing inversion in the regiochemical outcome of Diels–Alder reactions between Levoglucosenone ( 1 ) and its α-bromo derivative ( 5 ) with isoprene ( 2 ) was studied computationally. Based on different DFT calculations we concluded that both reactions should display the same regioselectivity. This result was further validated experimentally.
Victor V. Semenov - One of the best experts on this subject based on the ideXlab platform.
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Levoglucosenone-derived precursors for the stereoselective synthesis of methylene-expanded analogues of C-nucleosides
Mendeleev Communications, 2015Co-Authors: Valery K. Brel, Leonid D. Konyushkin, Aleksandr V. Samet, Adam I. Stash, Vitaly K. Belsky, Victor V. SemenovAbstract:Simple chiral precursors for the preparation of methylene-expanded C-nucleosides were developed, using as key steps pyrolysis of cellulose to Levoglucosenone followed by hydrogenation and introduction of vinyl and ethynyl fragments to the 2-position.
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A concise approach to chiral chromenes based on Levoglucosenone
Tetrahedron Letters, 2011Co-Authors: Аlexander V. Samet, Dmitriy N. Lutov, S. I. Firgang, K. A. Lyssenko, Victor V. SemenovAbstract:Abstract Levoglucosenone, a chiral α,β-unsaturated ketone derived from cellulose, undergoes a stereoselective domino oxa-Michael–aldol reaction with 2-hydroxybenzaldehydes affording optically active pyrano[3,4-b]chromenes. The latter are further converted into 2H-chromenes via a Beckmann fragmentation reaction.
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Preparation of chiral cyclopropanecarboxylic acids and 3-oxabicyclo[3.1.0]hexane-2-ones from Levoglucosenone
Tetrahedron-asymmetry, 2008Co-Authors: Alexander V. Samet, Leonid D. Konyushkin, Dmitriy N. Lutov, Yuri A. Strelenko, Victor V. SemenovAbstract:Levoglucosenone (a chiral α,β-unsaturated ketone derivative of cellulose) serves as a starting compound in 2 and 3 step syntheses of chiral cyclopropanecarboxylic acids and 3-oxabicyclo[3.1.0]hexane-2-ones, respectively.
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Preparation of chiral cyclopropanes with a carbohydrate fragment from Levoglucosenone
Tetrahedron: Asymmetry, 2007Co-Authors: Alexander V. Samet, A M Shestopalov, Dmitriy N. Lutov, Lyudmila A. Rodinovskaya, Alexander A. Shestopalov, Victor V. SemenovAbstract:Abstract Levoglucosenone (a chiral α,β-unsaturated ketone derivative of cellulose) underwent stereoselective cyclopropanation with sulfonium ylides to form chiral trisubstituted cyclopropanes annulated with the carbohydrate moiety in high yields.
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interaction of Levoglucosenone with malononitrile
Russian Chemical Bulletin, 1999Co-Authors: A. V. Samet, N B Chernysheva, A M Shestopalov, Victor V. SemenovAbstract:Levoglucosenone reacts with malononitrile to form a product with a complex structure, which contains two Levoglucosenone molecules and three malononitrile molecules. The conclusion about the structure of the product was based on the data of NMR, IR, and UV spectroscopy and mass spectrometry. The suggested reaction mechanism involves cascade cyclization.
Farid A. Valeev - One of the best experts on this subject based on the ideXlab platform.
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Michael Adducts of Levoglucosenone with α-Ethoxycarbonyl- and α-Nitrocyclododecanones: Transformation into Chiral Macrolides
Chemistry of Heterocyclic Compounds, 2020Co-Authors: L. Kh. Faizullina, Sh. M. Salikhov, Yulia S. Galimova, Farid A. ValeevAbstract:Levoglucosenone reacted with α-ethoxycarbonyl- and α-nitrocyclododecanones, leading to the formation of diastereomeric Michael adducts in high yields. Methods were developed for the denitration of the respective nitroadducts by treatment with Raney nickel and Bu3SnH, allowing to optimize the synthesis of a 16-membered chiral macrolide.
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Hydroxyderivatives of Levoglucosenone in reactions of enantioselective reduction of 1,3-diphenylpropan-1-one
Butlerov Communications, 2020Co-Authors: A. N. Davydova, B. T. Sharipov, Farid A. ValeevAbstract:The enantioselective reduction of prochiral ketones is an important method for the preparation of enanti-enriched secondary alcohols, which can serve as starting materials for optically active compounds. Chiral metal hydride reagents, such as lithium aluminum hydride (LiAlH4) and sodium borohydride (NaBH4), modified with chiral ligands, have been developed to effect enantioselective reduction. However, in most cases, derivatives are used to obtain chiral hydride reagents, which are rare and hardly available. Therefore, the search for more accessible and effective derivatives suitable for the modification of hydride reagents is an urgent task. Levoglucosenone is an optically pure enone of carbohydrate nature, readily available by pyrolysis of any cellulose-containing materials. Levoglucosenone is considered a promising bioplatform for both laboratory synthesis and industrial use. The prospect of the development of chemistry of Levoglucosenone and its derivatives in industry makes it possible to pay attention to these compounds from the point of view of studying their possibilities as chiral inducers or auxiliaries. In this work, we studied the possibilities of chiral induction in the reduction reactions of 1,3-diphenylpropan-1-one with hydride reagents obtained by replacing hydrogens in LiAlH4 and NaBH4 with hydroxy derivatives of Levoglucosenone. The reduction of 1,3-diphenylpropan-1-one with chiral aluminum hydride reagents proceeded with low enantioselectivity, mainly with a predominance of (S)-1,3-diphenylpropan-1-ol. It was found that the enantiomeric purity of the S-stereomer decreases with an increase in the substitution of hydrogen atoms in LiAlH4 by hydroxy derivatives of Levoglucosenone. Reduction of 1,3-diphenylpropan-1-one with reagents obtained by partial neutralization of NaBH4 with hydroxy derivatives of Levoglucosenone, on the contrary, predominantly leads to the formation of (R)-1,3-diphenylpropan-1-ol. The addition of AcOH and Bu4NCl to NaBH4 has a positive effect on the optical frequency of the R-alcohol. At the same time, enantioselectivity in the reactions was almost absent upon reduction of 1,3-diphenylpropan-1-one with reagents obtained by partial neutralization of BH3. The best results of enantioselective reduction were shown by unsaturated alcohols: (1S,4S,5R) -6,8-dioxabicyclo[3.2.1]oct-2-en-4-ol and (1S,4S,5R)-4-methyl-6,8-dioxabicyclo[3.2.1]oct-2-en-4-ol, of which (1S,4S,5R)-6,8-dioxabicyclo[3.2.1]oct-2-en-4-ol was the most effective. It is likely that an increase in the enantioselectivity of reactions carried out in the presence of hydroxy derivatives of Levoglucosenone is possible by obtaining more bulky chiral ligands, provided that the double bond is retained.
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Diels-Alder adduct of Levoglucosenone with diene Dane approaches to estrogens
Butlerov Communications, 2020Co-Authors: L. Kh. Faizullina, Yu. A. Khalilova, Yulia S. Galimova, Farid A. ValeevAbstract:Levoglucosenone has established itself as a good Michael acceptor and a powerful dienophile in Diels-Alder reactions, dipolar cycloaddition and in a number of other transformations. In the Diels-Alder reactions of Levoglucosenone with 1,3-dienes, chiral derivatives of cyclohexene are obtained, which are valuable products for the synthesis of natural compounds. We previously studied the reaction of the interaction of Levoglucosenone with Dane diene under catalytic, thermal conditions, at ultrahigh pressures and microwave irradiation. It was found that as a result of the reaction, 2 adducts are formed – (1S,2S,15S,17R)-9-methoxy-18,20-dioxapentacyclo[15.2.1.02,15.0.5,14.06,11]icosa-4,6,8, 10-tetraen-16-one and its isomer, the product of the double bond migration is (1S,2S,14S,15S,17R)-9-methoxy-18,20-dioxapentacyclo[15.2.1.02,15.0.5, 14.06,11]icosa-5(14), 6,8,10-tetraen-16-one. In this work, we have developed methods for the transformation of these Diels-Alder adducts in approaches to compounds with a steroid skeleton. Thus, based on the obtained Diels-Alder adducts, optically active hydrazone was synthesized. An optimal method for deoxygenation of a keto group proceeding by aromatization of cycle B in (1S,2S,14S,15S,17R)-9-methoxy-18,20-dioxapenta-cyclo[15.2.1.02,15.0.5,14.06,11]icosa-5(14),6,8,10-tetraen-16-one, converting it to sulfide, followed by boiling in the presence of Raney nickel. The resulting compound, 9-methoxy-18,20-dioxapentacyclo-[15.2.1.02,15.0.5, 14.06,11]icosa-5(14),6,8,10,12-pentaenone, is a promising synthetic block for use in the synthesis of estrogen – equilenin. The biological activity of the synthesized compounds was predicted using the PASS computer program, which resulted in the identification of derivatives that are promising for the study of antacid, anti-seborrheic, embryotoxic, and anti-cancer properties.
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Stereocontrolled synthesis of (9S)-ketodecanolide on the basis of Michael adducts obtained from Levoglucosenone and cyclohexanone
Chemistry of Heterocyclic Compounds, 2018Co-Authors: L. Kh. Faizullina, Sh. M. Salikhov, Yuliya A. Khalilova, Farid A. ValeevAbstract:A synthetic route was developed consisting of 10 steps for the synthesis of ketodecanolide with native topology in 11% overall yield, starting from Michael adducts of Levoglucosenone and cyclohexanone.
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Synthesis of sarcodictyin A analogue containing 14-methyl group and C(12)=C(13) bond in ring A from Levoglucosenone
Mendeleev Communications, 2017Co-Authors: B. T. Sharipov, A A Pershin, Farid A. ValeevAbstract:Starting from Levoglucosenone piperilene Diels–Alder adduct a total synthesis of sarcodictyin A analogue containing 14-methyl group and C(12)=C(13) bond in ring A was performed, where the key step was the intramolecular cyclization between acetylene and aldehyde moieties to produce a 10-membered carbocycle.
Ariel M. Sarotti - One of the best experts on this subject based on the ideXlab platform.
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Theoretical insight into the pyrolytic deformylation of Levoglucosenone and isoLevoglucosenone.
Carbohydrate research, 2014Co-Authors: Ariel M. SarottiAbstract:A computational study was conducted to gain insight into the pyrolytic deformylations of Levoglucosenone and isoLevoglucosenone. Present B3LYP/6-31G(∗) and CBS-QB3 calculations provide valuable evidence to rule out the formation of isoLevoglucosenone during the pyrolytic degradation of cellulosic materials. This, along with the supplementary data herein presented and with other recent reports, suggest that Levoglucosenone should not be formed directly from levoglucosan (as proposed in numerous reports), but rather from another intermediate, such as 1,4:3,6-dianhydro-α-d-glucopyranose.
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dft calculations induced a regiochemical outcome revision of the diels alder reaction between Levoglucosenone and isoprene
Tetrahedron Letters, 2011Co-Authors: Ariel M. Sarotti, Alejandra G Suarez, Rolando A. SpanevelloAbstract:Abstract An appealing inversion in the regiochemical outcome of Diels–Alder reactions between Levoglucosenone ( 1 ) and its α-bromo derivative ( 5 ) with isoprene ( 2 ) was studied computationally. Based on different DFT calculations we concluded that both reactions should display the same regioselectivity. This result was further validated experimentally.
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π stacking effect on Levoglucosenone derived internal chiral auxiliaries a case of complete enantioselectivity inversion on the diels alder reaction
Organic Letters, 2008Co-Authors: Ariel M. Sarotti, Rolando A. Spanevello, Israel Fernandez, Miguel A Sierra, Alejandra G SuarezAbstract:Detailed quantum chemical calculations, experimental evidence, and NMR data rationalize the participation of π-stacking interaction in the highly asymmetric Diels−Alder reaction using Levoglucosenone derived internal chiral auxiliaries, including the appealing effect of inversion of the enantioselectivity by coordination of the substrate with Et2AlCl.
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An efficient microwave-assisted green transformation of cellulose into Levoglucosenone. Advantages of the use of an experimental design approach
Green Chemistry, 2007Co-Authors: Ariel M. Sarotti, Rolando A. Spanevello, Alejandra G SuarezAbstract:The microwave-assisted pyrolysis of cellulose towards its conversion into Levoglucosenone is reported. An experimental design approach was used to find the variables involved in this transformation. Using this approach we established the optimal conditions to obtain the maximum yield of product.
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Microwave-Assisted Regioselective Cycloaddition Reactions between 9-Substituted Anthracenes and Levoglucosenone
Organic letters, 2006Co-Authors: Ariel M. Sarotti, Madeleine M. Joullié, And Rolando A. Spanevello, Alejandra G SuarezAbstract:The cycloaddition reactions of 9-substituted anthracenes and Levoglucosenone were investigated under microwave irradiation and conventional heating conditions. Considering time, yields, and regiose...