The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Françoise Colobert - One of the best experts on this subject based on the ideXlab platform.
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stereoselective synthesis of 2h chromans by Reductive Deoxygenation of differently substituted 2 sulfinylmethylchroman 2 ols
European Journal of Organic Chemistry, 2011Co-Authors: Antonio Urbano, Gloria Hernandeztorres, Carmen M Carreno, Françoise ColobertAbstract:Good-to-excellent diastereoselectivies have been achieved in the synthesis of 2H-chromans by Et3SiH/TMSOTf Reductive Deoxygenation of differently substituted 2-sulfinylmethylchroman-2-ols and their methyl ketals. The influence of both electron-donating and -withdrawing substituents on the sulfoxide and on the aromatic dihydobenzopyran core has been studied. SOR1 electron-donating groups (R1 = pMeOPh and 2-MeO-1-naphthyl) led to a competitive reaction in which the sulfoxide was reduced, thus lowering the yield of the sulfinyl 2H-chromans. The method allows the presence of different groups on the aromatic dihydrobenzopyran unit. The best results in terms of yield and diastereoselectivity were obtained with 2-[(p-tolylsulfinyl)methyl]chroman-2-ols. All the results are explained on mechanistic grounds. Synthetic transformations of the enantiopure 2H-chroman (S,RS)-21 are reported.
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Stereoselective Synthesis of 2H‐Chromans by Reductive Deoxygenation of Differently Substituted 2‐Sulfinylmethylchroman‐2‐ols
European Journal of Organic Chemistry, 2011Co-Authors: Gloria Hernández‐torres, M. Carmen Carreño, Antonio Urbano, Françoise ColobertAbstract:Good-to-excellent diastereoselectivies have been achieved in the synthesis of 2H-chromans by Et3SiH/TMSOTf Reductive Deoxygenation of differently substituted 2-sulfinylmethylchroman-2-ols and their methyl ketals. The influence of both electron-donating and -withdrawing substituents on the sulfoxide and on the aromatic dihydobenzopyran core has been studied. SOR1 electron-donating groups (R1 = pMeOPh and 2-MeO-1-naphthyl) led to a competitive reaction in which the sulfoxide was reduced, thus lowering the yield of the sulfinyl 2H-chromans. The method allows the presence of different groups on the aromatic dihydrobenzopyran unit. The best results in terms of yield and diastereoselectivity were obtained with 2-[(p-tolylsulfinyl)methyl]chroman-2-ols. All the results are explained on mechanistic grounds. Synthetic transformations of the enantiopure 2H-chroman (S,RS)-21 are reported.
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Sulfoxide-Directed Stereocontrolled Access to 2H-Chromans: Total Synthesis of the (S,R,R,R)-Enantiomer of the Antihypertensive Drug Nebivolol
European Journal of Organic Chemistry, 2008Co-Authors: M. Carmen Carreño, Antonio Urbano, Gloria Hernández-torres, Françoise ColobertAbstract:A homochiral sulfoxide-directed Reductive Deoxygenation of 2-(p-tolylsulfinyl)methyl-2-chromanols allows the stereoselective formation of 2H-chromans with up to 95:5 diastereoisomeric ratio. This new methodology was appliedin a short and convergent enantioselective synthesis ofthe (S,R,R,R)-enantiomer of the antihypertensive drugNebivolol.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
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Sulfoxide‐Directed Stereocontrolled Access to 2H‐Chromans: Total Synthesis of the (S,R,R,R)‐Enantiomer of the Antihypertensive Drug Nebivolol
European Journal of Organic Chemistry, 2008Co-Authors: M. Carmen Carreño, Antonio Urbano, Gloria Hernández-torres, Françoise ColobertAbstract:A homochiral sulfoxide-directed Reductive Deoxygenation of 2-(p-tolylsulfinyl)methyl-2-chromanols allows the stereoselective formation of 2H-chromans with up to 95:5 diastereoisomeric ratio. This new methodology was appliedin a short and convergent enantioselective synthesis ofthe (S,R,R,R)-enantiomer of the antihypertensive drugNebivolol.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Takeo Konakahara - One of the best experts on this subject based on the ideXlab platform.
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one step conversion to tertiary amines inbr3 et3sih mediated Reductive Deoxygenation of tertiary amides
Tetrahedron Letters, 2008Co-Authors: Norio Sakai, Kohji Fujii, Takeo KonakaharaAbstract:Abstract We have developed a simple and practical procedure for a direct Reductive conversion from a variety of tertiary amides to the corresponding tertiary amines using an InBr3/Et3SiH reducing system. This reducing system can be applied to the reduction of a secondary amide and provides a more efficient alternative to conventional methods that use aluminum and boron hydrides.
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One-step conversion to tertiary amines : InBr3/Et3SiH-mediated Reductive Deoxygenation of tertiary amides
Tetrahedron Letters, 2008Co-Authors: Norio Sakai, Kohji Fujii, Takeo KonakaharaAbstract:Abstract We have developed a simple and practical procedure for a direct Reductive conversion from a variety of tertiary amides to the corresponding tertiary amines using an InBr3/Et3SiH reducing system. This reducing system can be applied to the reduction of a secondary amide and provides a more efficient alternative to conventional methods that use aluminum and boron hydrides.
Norio Sakai - One of the best experts on this subject based on the ideXlab platform.
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one step conversion to tertiary amines inbr3 et3sih mediated Reductive Deoxygenation of tertiary amides
Tetrahedron Letters, 2008Co-Authors: Norio Sakai, Kohji Fujii, Takeo KonakaharaAbstract:Abstract We have developed a simple and practical procedure for a direct Reductive conversion from a variety of tertiary amides to the corresponding tertiary amines using an InBr3/Et3SiH reducing system. This reducing system can be applied to the reduction of a secondary amide and provides a more efficient alternative to conventional methods that use aluminum and boron hydrides.
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One-step conversion to tertiary amines : InBr3/Et3SiH-mediated Reductive Deoxygenation of tertiary amides
Tetrahedron Letters, 2008Co-Authors: Norio Sakai, Kohji Fujii, Takeo KonakaharaAbstract:Abstract We have developed a simple and practical procedure for a direct Reductive conversion from a variety of tertiary amides to the corresponding tertiary amines using an InBr3/Et3SiH reducing system. This reducing system can be applied to the reduction of a secondary amide and provides a more efficient alternative to conventional methods that use aluminum and boron hydrides.
Naseem Ahmed - One of the best experts on this subject based on the ideXlab platform.
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Mild and Efficient Reductive Deoxygenation of Epoxides to Olefins with Tin(II) Chloride/Sodium Iodide as a Novel Reagent
Synthesis, 2015Co-Authors: Gulab Khushalrao Pathe, Naseem AhmedAbstract:A highly efficient and green protocol is reported for the Reductive Deoxygenation of organic epoxides to olefins using tin(II) chloride/sodium iodide as a novel reagent. The reaction gives an excellent yield (85–96%) in ethanol under reflux within 2–10 minutes, without affecting other functional groups. The advantages of our method are the use of inexpensive reagents, the eco-friendly and green reaction conditions, and the short reaction times and high yields.
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mild and efficient Reductive Deoxygenation of epoxides to olefins with tin ii chloride sodium iodide as a novel reagent
Synthesis, 2015Co-Authors: Gulab Khushalrao Pathe, Naseem AhmedAbstract:A highly efficient and green protocol is reported for the Reductive Deoxygenation of organic epoxides to olefins using tin(II) chloride/sodium iodide as a novel reagent. The reaction gives an excellent yield (85–96%) in ethanol under reflux within 2–10 minutes, without affecting other functional groups. The advantages of our method are the use of inexpensive reagents, the eco-friendly and green reaction conditions, and the short reaction times and high yields.
Antonio Urbano - One of the best experts on this subject based on the ideXlab platform.
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stereoselective synthesis of 2h chromans by Reductive Deoxygenation of differently substituted 2 sulfinylmethylchroman 2 ols
European Journal of Organic Chemistry, 2011Co-Authors: Antonio Urbano, Gloria Hernandeztorres, Carmen M Carreno, Françoise ColobertAbstract:Good-to-excellent diastereoselectivies have been achieved in the synthesis of 2H-chromans by Et3SiH/TMSOTf Reductive Deoxygenation of differently substituted 2-sulfinylmethylchroman-2-ols and their methyl ketals. The influence of both electron-donating and -withdrawing substituents on the sulfoxide and on the aromatic dihydobenzopyran core has been studied. SOR1 electron-donating groups (R1 = pMeOPh and 2-MeO-1-naphthyl) led to a competitive reaction in which the sulfoxide was reduced, thus lowering the yield of the sulfinyl 2H-chromans. The method allows the presence of different groups on the aromatic dihydrobenzopyran unit. The best results in terms of yield and diastereoselectivity were obtained with 2-[(p-tolylsulfinyl)methyl]chroman-2-ols. All the results are explained on mechanistic grounds. Synthetic transformations of the enantiopure 2H-chroman (S,RS)-21 are reported.
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Stereoselective Synthesis of 2H‐Chromans by Reductive Deoxygenation of Differently Substituted 2‐Sulfinylmethylchroman‐2‐ols
European Journal of Organic Chemistry, 2011Co-Authors: Gloria Hernández‐torres, M. Carmen Carreño, Antonio Urbano, Françoise ColobertAbstract:Good-to-excellent diastereoselectivies have been achieved in the synthesis of 2H-chromans by Et3SiH/TMSOTf Reductive Deoxygenation of differently substituted 2-sulfinylmethylchroman-2-ols and their methyl ketals. The influence of both electron-donating and -withdrawing substituents on the sulfoxide and on the aromatic dihydobenzopyran core has been studied. SOR1 electron-donating groups (R1 = pMeOPh and 2-MeO-1-naphthyl) led to a competitive reaction in which the sulfoxide was reduced, thus lowering the yield of the sulfinyl 2H-chromans. The method allows the presence of different groups on the aromatic dihydrobenzopyran unit. The best results in terms of yield and diastereoselectivity were obtained with 2-[(p-tolylsulfinyl)methyl]chroman-2-ols. All the results are explained on mechanistic grounds. Synthetic transformations of the enantiopure 2H-chroman (S,RS)-21 are reported.
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Sulfoxide-Directed Stereocontrolled Access to 2H-Chromans: Total Synthesis of the (S,R,R,R)-Enantiomer of the Antihypertensive Drug Nebivolol
European Journal of Organic Chemistry, 2008Co-Authors: M. Carmen Carreño, Antonio Urbano, Gloria Hernández-torres, Françoise ColobertAbstract:A homochiral sulfoxide-directed Reductive Deoxygenation of 2-(p-tolylsulfinyl)methyl-2-chromanols allows the stereoselective formation of 2H-chromans with up to 95:5 diastereoisomeric ratio. This new methodology was appliedin a short and convergent enantioselective synthesis ofthe (S,R,R,R)-enantiomer of the antihypertensive drugNebivolol.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
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Sulfoxide‐Directed Stereocontrolled Access to 2H‐Chromans: Total Synthesis of the (S,R,R,R)‐Enantiomer of the Antihypertensive Drug Nebivolol
European Journal of Organic Chemistry, 2008Co-Authors: M. Carmen Carreño, Antonio Urbano, Gloria Hernández-torres, Françoise ColobertAbstract:A homochiral sulfoxide-directed Reductive Deoxygenation of 2-(p-tolylsulfinyl)methyl-2-chromanols allows the stereoselective formation of 2H-chromans with up to 95:5 diastereoisomeric ratio. This new methodology was appliedin a short and convergent enantioselective synthesis ofthe (S,R,R,R)-enantiomer of the antihypertensive drugNebivolol.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
