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Rafael Suau - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of New Dopamine D1 Antagonist SCH 23390 Analogues by the Stereoselective Stevens Rearrangement
European Journal of Organic Chemistry, 2011Co-Authors: Manuela Ariza, Amelia Díaz, Rafael Suau, Maria ValpuestaAbstract:A convenient synthesis for new SCH 23390 analogues bearing different substituents at the C-1 position has been developed by using the diastereoselective Stevens Rearrangement. This procedure has provided a good number of new 1,2-disubstituted 1H-3-benzazepines, either through isolation of the isoquinolinium salts or directly by using a new one-pot N-alkylation–Stevens Rearrangement reaction.
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diastereoselective synthesis of 1 2 disubstituted 2 3 4 5 tetrahydro 1h 3 benzazepines by means of the Stevens Rearrangement
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Rafael SuauAbstract:1,2-Disubstituted 2,3,4,5-tetrahydro-1H-3-benzazepines were conveniently obtained by making use of the regio- and diastereoselective Stevens Rearrangement of the corresponding isoquinolinium salts with 1,8-diazabicyclo[5.4.0]undec-7-ene in acetonitrile. This procedure has provided a good number of novel analogue compounds of SCH 23390.
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Diastereoselective Synthesis of 1,2‐Disubstituted 2,3,4,5‐Tetrahydro‐1H‐3‐benzazepines by Means of the Stevens Rearrangement
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Rafael SuauAbstract:1,2-Disubstituted 2,3,4,5-tetrahydro-1H-3-benzazepines were conveniently obtained by making use of the regio- and diastereoselective Stevens Rearrangement of the corresponding isoquinolinium salts with 1,8-diazabicyclo[5.4.0]undec-7-ene in acetonitrile. This procedure has provided a good number of novel analogue compounds of SCH 23390.
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Total Synthesis of New 8‐(Arylmethyl)berbines
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Gregorio Torres, Rafael SuauAbstract:The total synthesis of the natural compound (8S * ,14S * )-8-(4'-hydroxybenzyl)-2,3-dimethoxyberbin-10-ol and its C-8 epimer has been conveniently developed by making use of the diastereoselective Stevens Rearrangement of the corresponding N-(arylmethyl)berbinium salts as the key step.
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Regio‐ and Stereoselective Stevens Rearrangement of Benzyltetrahydroprotoberberinium Salts
European Journal of Organic Chemistry, 2004Co-Authors: Maria Valpuesta, Amelia Díaz, Rafael Suau, Gregorio TorresAbstract:8-(Arylmethyl)berbines are conveniently obtained through a Stevens Rearrangement of the corresponding N-arylmethylberbinium salts with sodium methylsulfinylmethylide in DMSO. This procedure has provided two new nonnatural 8-benzylcanadines stereoselectively, without competition from the Hofmann elimination. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Maria Valpuesta - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of New Dopamine D1 Antagonist SCH 23390 Analogues by the Stereoselective Stevens Rearrangement
European Journal of Organic Chemistry, 2011Co-Authors: Manuela Ariza, Amelia Díaz, Rafael Suau, Maria ValpuestaAbstract:A convenient synthesis for new SCH 23390 analogues bearing different substituents at the C-1 position has been developed by using the diastereoselective Stevens Rearrangement. This procedure has provided a good number of new 1,2-disubstituted 1H-3-benzazepines, either through isolation of the isoquinolinium salts or directly by using a new one-pot N-alkylation–Stevens Rearrangement reaction.
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diastereoselective synthesis of 1 2 disubstituted 2 3 4 5 tetrahydro 1h 3 benzazepines by means of the Stevens Rearrangement
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Rafael SuauAbstract:1,2-Disubstituted 2,3,4,5-tetrahydro-1H-3-benzazepines were conveniently obtained by making use of the regio- and diastereoselective Stevens Rearrangement of the corresponding isoquinolinium salts with 1,8-diazabicyclo[5.4.0]undec-7-ene in acetonitrile. This procedure has provided a good number of novel analogue compounds of SCH 23390.
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Diastereoselective Synthesis of 1,2‐Disubstituted 2,3,4,5‐Tetrahydro‐1H‐3‐benzazepines by Means of the Stevens Rearrangement
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Rafael SuauAbstract:1,2-Disubstituted 2,3,4,5-tetrahydro-1H-3-benzazepines were conveniently obtained by making use of the regio- and diastereoselective Stevens Rearrangement of the corresponding isoquinolinium salts with 1,8-diazabicyclo[5.4.0]undec-7-ene in acetonitrile. This procedure has provided a good number of novel analogue compounds of SCH 23390.
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Total Synthesis of New 8‐(Arylmethyl)berbines
European Journal of Organic Chemistry, 2010Co-Authors: Maria Valpuesta, Manuela Ariza, Amelia Díaz, Gregorio Torres, Rafael SuauAbstract:The total synthesis of the natural compound (8S * ,14S * )-8-(4'-hydroxybenzyl)-2,3-dimethoxyberbin-10-ol and its C-8 epimer has been conveniently developed by making use of the diastereoselective Stevens Rearrangement of the corresponding N-(arylmethyl)berbinium salts as the key step.
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Regio‐ and Stereoselective Stevens Rearrangement of Benzyltetrahydroprotoberberinium Salts
European Journal of Organic Chemistry, 2004Co-Authors: Maria Valpuesta, Amelia Díaz, Rafael Suau, Gregorio TorresAbstract:8-(Arylmethyl)berbines are conveniently obtained through a Stevens Rearrangement of the corresponding N-arylmethylberbinium salts with sodium methylsulfinylmethylide in DMSO. This procedure has provided two new nonnatural 8-benzylcanadines stereoselectively, without competition from the Hofmann elimination. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Uttam K. Tambar - One of the best experts on this subject based on the ideXlab platform.
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Stereoselective Synthesis of Functionalized Cyclic Amino Acid Derivatives via a [2,3]-Stevens Rearrangement and Ring-Closing Metathesis.
ChemInform, 2014Co-Authors: Aaron Nash, Arash Soheili, Uttam K. TambarAbstract:Unnatural cyclic amino acid derivatives are accessible through a palladium-catalyzed tandem allylic amination/Stevens Rearrangement followed by ring-closing metathesis.
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synthesis of amathaspiramide f stereochemical switch of a 2 3 Stevens Rearrangement
2014Co-Authors: Arash Soheili, Carrie Johnson, Uttam K. TambarAbstract:Abstract The total synthesis of complex natural products provides a unique opportunity for learning new lessons in chemical reactivity, which drives the field of synthesis forward. With this goal in mind, we describe our synthetic approach to (±)-amathaspiramide F, a polycyclic alkaloid. The key transformation in our strategy is a tandem palladium-catalyzed allylic amination/[2,3]-Stevens Rearrangement, which was recently developed by our lab. Although our retrosynthetic analysis for the amathaspiramides was at first glance straightforward, we uncovered an unusual stereochemical effect that led us down an unexpected path to eventually solve the problem and complete the synthesis of amathaspiramide F. The unexpected diastereoselectivity of the [2,3]-Stevens Rearrangement was controlled by the substitution patterns of an aromatic ring. This stereochemical switch may represent a new stereocontrolling element for [2,3]-sigmatropic Rearrangements in complex molecular settings.
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Chapter 6 - Synthesis of (±)-Amathaspiramide F: Stereochemical Switch of a [2,3]-Stevens Rearrangement
Strategies and Tactics in Organic Synthesis, 2014Co-Authors: Arash Soheili, Carrie Johnson, Uttam K. TambarAbstract:The total synthesis of complex natural products provides a unique opportunity for learning new lessons in chemical reactivity, which drives the field of synthesis forward. With this goal in mind, we describe our synthetic approach to (±)-amathaspiramide F, a polycyclic alkaloid. The key transformation in our strategy is a tandem palladium-catalyzed allylic amination/[2,3]-Stevens Rearrangement, which was recently developed by our lab. Although our retrosynthetic analysis for the amathaspiramides was at first glance straightforward, we uncovered an unusual stereochemical effect that led us down an unexpected path to eventually solve the problem and complete the synthesis of amathaspiramide F. The unexpected diastereoselectivity of the [2,3]-Stevens Rearrangement was controlled by the substitution patterns of an aromatic ring. This stereochemical switch may represent a new stereocontrolling element for [2,3]-sigmatropic Rearrangements in complex molecular settings.
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chapter 6 synthesis of amathaspiramide f stereochemical switch of a 2 3 Stevens Rearrangement
Strategies and Tactics in Organic Synthesis, 2014Co-Authors: Arash Soheili, Carrie Johnson, Uttam K. TambarAbstract:The total synthesis of complex natural products provides a unique opportunity for learning new lessons in chemical reactivity, which drives the field of synthesis forward. With this goal in mind, we describe our synthetic approach to (±)-amathaspiramide F, a polycyclic alkaloid. The key transformation in our strategy is a tandem palladium-catalyzed allylic amination/[2,3]-Stevens Rearrangement, which was recently developed by our lab. Although our retrosynthetic analysis for the amathaspiramides was at first glance straightforward, we uncovered an unusual stereochemical effect that led us down an unexpected path to eventually solve the problem and complete the synthesis of amathaspiramide F. The unexpected diastereoselectivity of the [2,3]-Stevens Rearrangement was controlled by the substitution patterns of an aromatic ring. This stereochemical switch may represent a new stereocontrolling element for [2,3]-sigmatropic Rearrangements in complex molecular settings.
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Synthesis of (±)-amathaspiramide F and discovery of an unusual stereocontrolling element for the [2,3]-Stevens Rearrangement
Organic letters, 2013Co-Authors: Arash Soheili, Uttam K. TambarAbstract:A formal total synthesis of (±)-amathaspiramide F through a tandem palladium-catalyzed allylic amination/[2,3]-Stevens Rearrangement is reported. The unexpected diastereoselectivity of the [2,3]-Stevens Rearrangement was controlled by the substitution patterns of an aromatic ring. This discovery represents a new stereocontrolling element for [2,3]-sigmatropic Rearrangements in complex molecular settings.
Till Opatz - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Alkaloids by Stevens Rearrangement of Nitrile-Stabilized Ammonium Ylides: (±)-Laudanosine, (±)-Laudanidine, (±)-Armepavine, (±)-7-Methoxycryptopleurine, and (±)-Xylopinine
The Journal of organic chemistry, 2013Co-Authors: Julio Cesar Orejarena Pacheco, Günther Lahm, Till OpatzAbstract:The Stevens Rearrangement of nitrile-stabilized ammonium ylides in conjunction with the reductive removal of the nitrile function permits the facile construction of α-branched amines from α-aminonitriles. We employed this reaction sequence for the preparation of (±)-laudanosine, (±)-laudanidine and (±)-armepavine, (±)-7-methoxycryptopleurine, and (±)-xylopinine from two closely related and readily accessible bicyclic α-aminonitriles. The final products were obtained in high to almost quantitative yields (71–98%) from the quaternary ammonium salts obtained by N-alkylation of these starting materials.
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synthesis of alkaloids by Stevens Rearrangement of nitrile stabilized ammonium ylides laudanosine laudanidine armepavine 7 methoxycryptopleurine and xylopinine
Journal of Organic Chemistry, 2013Co-Authors: Julio Cesar Orejarena Pacheco, Günther Lahm, Till OpatzAbstract:The Stevens Rearrangement of nitrile-stabilized ammonium ylides in conjunction with the reductive removal of the nitrile function permits the facile construction of α-branched amines from α-aminonitriles. We employed this reaction sequence for the preparation of (±)-laudanosine, (±)-laudanidine and (±)-armepavine, (±)-7-methoxycryptopleurine, and (±)-xylopinine from two closely related and readily accessible bicyclic α-aminonitriles. The final products were obtained in high to almost quantitative yields (71–98%) from the quaternary ammonium salts obtained by N-alkylation of these starting materials.
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Synthesis of Alkaloids by Stevens Rearrangement of Nitrile-Stabilized Ammonium Ylides: (±)-Laudanosine, (±)-Laudanidine, (±)-Armepavine, (±)-7-Methoxycryptopleurine, and (±)-Xylopinine
2013Co-Authors: Julio Cesar Orejarena Pacheco, Günther Lahm, Till OpatzAbstract:The Stevens Rearrangement of nitrile-stabilized ammonium ylides in conjunction with the reductive removal of the nitrile function permits the facile construction of α-branched amines from α-aminonitriles. We employed this reaction sequence for the preparation of (±)-laudanosine, (±)-laudanidine and (±)-armepavine, (±)-7-methoxycryptopleurine, and (±)-xylopinine from two closely related and readily accessible bicyclic α-aminonitriles. The final products were obtained in high to almost quantitative yields (71–98%) from the quaternary ammonium salts obtained by N-alkylation of these starting materials
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A five-step synthesis of (±)-tylophorine via a nitrile-stabilized ammonium ylide.
The Journal of organic chemistry, 2012Co-Authors: Günther Lahm, Alexander Stoye, Till OpatzAbstract:The Stevens Rearrangement of a nitrile-stabilized ammonium ylide is the key step of a very short and practical synthesis of the phenanthroindolizine alkaloid (±)-tylophorine. The method requires only five linear steps and is devoid of any protecting group manipulations.
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A Five-Step Synthesis of (±)-Tylophorine via a Nitrile-Stabilized Ammonium Ylide
2012Co-Authors: Günther Lahm, Alexander Stoye, Till OpatzAbstract:The Stevens Rearrangement of a nitrile-stabilized ammonium ylide is the key step of a very short and practical synthesis of the phenanthroindolizine alkaloid (±)-tylophorine. The method requires only five linear steps and is devoid of any protecting group manipulations
Zhanzhu Liu - One of the best experts on this subject based on the ideXlab platform.
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A concise synthesis of (E)-3-aryl-2,3,4,5-tetrahydro-1H-3-benzazonines by aryne induced [2,3] Stevens Rearrangement of 1,2,3,4-tetrahydroisoquinolines.
Organic & biomolecular chemistry, 2018Co-Authors: Xuan Pan, Zhanzhu LiuAbstract:A mild and transition-metal-free approach for the synthesis of (E)-3-aryl-2,3,4,5-tetrahydro-1H-3-benzazonines via [2,3] Stevens Rearrangement of 1,2,3,4-tetrahydroisoquinolines with arynes is described. This protocol provides straightforward access to (E)-3-aryl-2,3,4,5-tetrahydro-1H-3-benzazonines in moderate to good yields with excellent diastereoselectivity. A broad range of functional groups, involving nitrile, esters, ketone and aryl halide, were well tolerated in this reaction.
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Synthesis of 3-aryl-3-benzazepines via aryne [1,2] Stevens Rearrangement of 1,2,3,4-tetrahydroisoquinolines
Organic Chemistry Frontiers, 2018Co-Authors: Xuan Pan, Zhanzhu LiuAbstract:An efficient method for the synthesis of 3-aryl-3-benzazepines via aryne induced [1,2] Stevens Rearrangement of 1,2,3,4-tetrahydroisoquinolines is described. This approach provided straightforward access to 3-aryl-3-benzazepines in moderate to good yields under transition-metal-free and strong-base-free conditions. Temperature-dependent α-arylated products of the carbonyl group were also obtained. Preliminary mechanistic studies suggest both 3-aryl-3-benzazepines and α-arylated products of the carbonyl group were generated via the Rearrangement of nitrogen ylide intermediates.