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Maria J. Alves - One of the best experts on this subject based on the ideXlab platform.
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a short synthesis of 2s 3s 4r dihydroxyhomoprolines from d Erythrose derived 5 6 dihydro 2h pyran 2 one
Synthesis, 2019Co-Authors: David S. Freitas, Jennifer Noro, Antonio Gil Fortes, Artem Drogalin, Monica C S Fernandes, Antonio V M Baptista, Joana Parente, Jose E Rodriguezborges, Maria J. AlvesAbstract:(2S,3S,4R)-Dihydroxyhomoprolines were obtained from a six-carbon-atom lactone intermediate obtained from d -Erythrose in a short synthesis, by facile operational methodology, in very good overall yields.
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Total Stereoselective Michael Addition of N- and S- Nucleophiles to a d‑Erythrosyl 1,5-Lactone Derivative. Experimental and Theoretical Studies Devoted to the Synthesis of 2,6-Dideoxy-4-functionalized‑d-ribono-hexono-1,4-lactone
2018Co-Authors: Juliana F. Rocha, David S. Freitas, Jennifer Noro, Carla Silva S. Teixeira, Cristina E. A. Sousa, Maria J. Alves, Nuno M. F. S. A. CerqueiraAbstract:The synthesis of a 1,5-lactone 2,4-O-alkylidene-d-Erythrose derivative was found to be a highly stereoselective template in Michael addition trough the reaction of a d-erythrosyl 1,5-lactone derivative with nitrogen and sulfur nucleophiles. The sulfur adducts formed are 1 (d-Erythrose derivative):1 (nucleophile), and the nitrogen adducts are 1:2. Both were then treated under HCl to give 2,6-dideoxy-4-functionalized-d-ribono-hexono-1,4-lactone by a reaction cascade in high overall yield. Reaction’s scale up even improves the yield. The theoretical and computational results clearly explain the origin of the stereoselectivity, and the energetic course of reactions starting with nitrogen and sulfide nucleophiles. Considering that the 1,4-lactones obtained in this work offer a new molecular scaffold for organic synthesis, these new results provide a solid theoretical platform that can be used to speed up synthesis of other derivatives in a stereo- and regioselective way
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
ChemInform, 2014Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:The Diels—Alder reaction of D-Erythrose derived 1,3-butadienes (II) with tert-butyl 2H-aziridine 3-carboxylate, generated in situ by from azide (I), is described.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
Tetrahedron-asymmetry, 2013Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:Abstract Two d -Erythrose 1,3-butadienes were reacted with electrophilic achiral t- butyl 2 H -azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major ( R )-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral ( R )- and ( S )-products by changing the chiral nature of an extra chiral BINOL inductor used.
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diastereo controlled diels alder cycloadditions of Erythrose benzylidene acetal 1 3 butadienes by 4 substituted 1 2 4 triazoline 3 5 dione evidence for the stereoelectronic effects on the dienes
Tetrahedron-asymmetry, 2010Co-Authors: Maria J. Alves, Vera C M Duarte, Helio Faustino, Antonio Gil FortesAbstract:Abstract Erythrose benzylidene-acetal 1,3-butadienes are studied as partners in Diels–Alder cycloadditions. A high diastereofacial improvement is found in cases where both the alcohol function is protected and a π–π interaction between the diene and dienophile is possible. Several competing factors have been studied independently in order to explain its influence on the selectivity of the cycloadditions.
Antonio Gil Fortes - One of the best experts on this subject based on the ideXlab platform.
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a short synthesis of 2s 3s 4r dihydroxyhomoprolines from d Erythrose derived 5 6 dihydro 2h pyran 2 one
Synthesis, 2019Co-Authors: David S. Freitas, Jennifer Noro, Antonio Gil Fortes, Artem Drogalin, Monica C S Fernandes, Antonio V M Baptista, Joana Parente, Jose E Rodriguezborges, Maria J. AlvesAbstract:(2S,3S,4R)-Dihydroxyhomoprolines were obtained from a six-carbon-atom lactone intermediate obtained from d -Erythrose in a short synthesis, by facile operational methodology, in very good overall yields.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
ChemInform, 2014Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:The Diels—Alder reaction of D-Erythrose derived 1,3-butadienes (II) with tert-butyl 2H-aziridine 3-carboxylate, generated in situ by from azide (I), is described.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
Tetrahedron-asymmetry, 2013Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:Abstract Two d -Erythrose 1,3-butadienes were reacted with electrophilic achiral t- butyl 2 H -azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major ( R )-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral ( R )- and ( S )-products by changing the chiral nature of an extra chiral BINOL inductor used.
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diastereo controlled diels alder cycloadditions of Erythrose benzylidene acetal 1 3 butadienes by 4 substituted 1 2 4 triazoline 3 5 dione evidence for the stereoelectronic effects on the dienes
Tetrahedron-asymmetry, 2010Co-Authors: Maria J. Alves, Vera C M Duarte, Helio Faustino, Antonio Gil FortesAbstract:Abstract Erythrose benzylidene-acetal 1,3-butadienes are studied as partners in Diels–Alder cycloadditions. A high diastereofacial improvement is found in cases where both the alcohol function is protected and a π–π interaction between the diene and dienophile is possible. Several competing factors have been studied independently in order to explain its influence on the selectivity of the cycloadditions.
Nuno M Micaelo - One of the best experts on this subject based on the ideXlab platform.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
ChemInform, 2014Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:The Diels—Alder reaction of D-Erythrose derived 1,3-butadienes (II) with tert-butyl 2H-aziridine 3-carboxylate, generated in situ by from azide (I), is described.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
Tetrahedron-asymmetry, 2013Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:Abstract Two d -Erythrose 1,3-butadienes were reacted with electrophilic achiral t- butyl 2 H -azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major ( R )-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral ( R )- and ( S )-products by changing the chiral nature of an extra chiral BINOL inductor used.
Vera C M Duarte - One of the best experts on this subject based on the ideXlab platform.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
ChemInform, 2014Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:The Diels—Alder reaction of D-Erythrose derived 1,3-butadienes (II) with tert-butyl 2H-aziridine 3-carboxylate, generated in situ by from azide (I), is described.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
Tetrahedron-asymmetry, 2013Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:Abstract Two d -Erythrose 1,3-butadienes were reacted with electrophilic achiral t- butyl 2 H -azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major ( R )-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral ( R )- and ( S )-products by changing the chiral nature of an extra chiral BINOL inductor used.
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diastereo controlled diels alder cycloadditions of Erythrose benzylidene acetal 1 3 butadienes by 4 substituted 1 2 4 triazoline 3 5 dione evidence for the stereoelectronic effects on the dienes
Tetrahedron-asymmetry, 2010Co-Authors: Maria J. Alves, Vera C M Duarte, Helio Faustino, Antonio Gil FortesAbstract:Abstract Erythrose benzylidene-acetal 1,3-butadienes are studied as partners in Diels–Alder cycloadditions. A high diastereofacial improvement is found in cases where both the alcohol function is protected and a π–π interaction between the diene and dienophile is possible. Several competing factors have been studied independently in order to explain its influence on the selectivity of the cycloadditions.
Helio Faustino - One of the best experts on this subject based on the ideXlab platform.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
ChemInform, 2014Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:The Diels—Alder reaction of D-Erythrose derived 1,3-butadienes (II) with tert-butyl 2H-aziridine 3-carboxylate, generated in situ by from azide (I), is described.
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asymmetric diels alder cycloadditions of d Erythrose 1 3 butadienes to achiral t butyl 2h azirine 3 carboxylate
Tetrahedron-asymmetry, 2013Co-Authors: Vera C M Duarte, Maria J. Alves, Helio Faustino, Antonio Gil Fortes, Nuno M MicaeloAbstract:Abstract Two d -Erythrose 1,3-butadienes were reacted with electrophilic achiral t- butyl 2 H -azirine 3-carboxylate giving cycloadducts with good yields and moderate selectivity. The isomers could be separated to give the major ( R )-isomers at C-2 in approximately 50% yield in both cases. Alternatively LACASA-DA methodology was applied to one of the reactions leading to homochiral ( R )- and ( S )-products by changing the chiral nature of an extra chiral BINOL inductor used.
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diastereo controlled diels alder cycloadditions of Erythrose benzylidene acetal 1 3 butadienes by 4 substituted 1 2 4 triazoline 3 5 dione evidence for the stereoelectronic effects on the dienes
Tetrahedron-asymmetry, 2010Co-Authors: Maria J. Alves, Vera C M Duarte, Helio Faustino, Antonio Gil FortesAbstract:Abstract Erythrose benzylidene-acetal 1,3-butadienes are studied as partners in Diels–Alder cycloadditions. A high diastereofacial improvement is found in cases where both the alcohol function is protected and a π–π interaction between the diene and dienophile is possible. Several competing factors have been studied independently in order to explain its influence on the selectivity of the cycloadditions.