The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Wolfgang Steglich - One of the best experts on this subject based on the ideXlab platform.
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esterification of carboxylic acids with dicyclohexylcarbodiimide 4 Dimethylaminopyridine tert butyl ethyl fumarate
Organic Syntheses, 2003Co-Authors: B Neises, Wolfgang SteglichAbstract:Esterification of carboxylic acids with dicyclohexylcarbodiimide/4-Dimethylaminopyridine: tert-butyl ethyl fumarate reactant: 45.59 g (0.22 mol) of dicyclohexylcarbodiimide product: tert-butyl ethyl fumarate Keywords: esterification, of dicarboxylic acids; dichloromethane (methylene chloride); dicyclohexylcarbodiimide; dicyclohexylcarbodiimide
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Organic Syntheses - Esterification of Carboxylic Acids with Dicyclohexylcarbodiimide/4‐Dimethylaminopyridine: tert‐Butyl Ethyl Fumarate
Organic Syntheses, 2003Co-Authors: B Neises, Wolfgang SteglichAbstract:Esterification of carboxylic acids with dicyclohexylcarbodiimide/4-Dimethylaminopyridine: tert-butyl ethyl fumarate reactant: 45.59 g (0.22 mol) of dicyclohexylcarbodiimide product: tert-butyl ethyl fumarate Keywords: esterification, of dicarboxylic acids; dichloromethane (methylene chloride); dicyclohexylcarbodiimide; dicyclohexylcarbodiimide
B Neises - One of the best experts on this subject based on the ideXlab platform.
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esterification of carboxylic acids with dicyclohexylcarbodiimide 4 Dimethylaminopyridine tert butyl ethyl fumarate
Organic Syntheses, 2003Co-Authors: B Neises, Wolfgang SteglichAbstract:Esterification of carboxylic acids with dicyclohexylcarbodiimide/4-Dimethylaminopyridine: tert-butyl ethyl fumarate reactant: 45.59 g (0.22 mol) of dicyclohexylcarbodiimide product: tert-butyl ethyl fumarate Keywords: esterification, of dicarboxylic acids; dichloromethane (methylene chloride); dicyclohexylcarbodiimide; dicyclohexylcarbodiimide
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Organic Syntheses - Esterification of Carboxylic Acids with Dicyclohexylcarbodiimide/4‐Dimethylaminopyridine: tert‐Butyl Ethyl Fumarate
Organic Syntheses, 2003Co-Authors: B Neises, Wolfgang SteglichAbstract:Esterification of carboxylic acids with dicyclohexylcarbodiimide/4-Dimethylaminopyridine: tert-butyl ethyl fumarate reactant: 45.59 g (0.22 mol) of dicyclohexylcarbodiimide product: tert-butyl ethyl fumarate Keywords: esterification, of dicarboxylic acids; dichloromethane (methylene chloride); dicyclohexylcarbodiimide; dicyclohexylcarbodiimide
Ingo Pantenburg - One of the best experts on this subject based on the ideXlab platform.
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silver compounds in synthetic chemistry part 8 complexes of perfluoroorgano silver i derivatives with 4 Dimethylaminopyridine dmap
Zeitschrift für anorganische und allgemeine Chemie, 2014Co-Authors: Silke Kremer, Ingo Pantenburg, Wieland TyrraAbstract:Attempted syntheses of AgRf·DMAP were performed using the established route starting from AgF and Me3SiRf (Rf = CF3, C2F5, C6F5) followed by the addition of DMAP. Unexpectedly, reactions with perfluoroalkylsilver(I) derivatives yielded products, which underwent known equilibria, while exclusively the pentafluorophenyl derivative exhibits its zwitterionic nature in solution and in the solid state. Moreover, both perfluoroalkyl derivatives investigated decomposed slowly but more or less selectively even at –20 °C in solution: AgC2F5·DMAP mainly into AgOCOCF3 (probably under the influence of moisture) and AgCF3·DMAP mainly into the unprecedented derivative 3-trifluoromethyl-4-Dimethylaminopyridine. The molecular structure of AgC6F5·DMAP was elucidated showing a twist arrangement of the aromatic rings quite unusual for linear coordinated species.
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syntheses and crystal structures of bis 4 Dimethylaminopyridine group 12 trifluoroacetates m ococf3 2 2dmap m zn cd hg
Journal of Fluorine Chemistry, 2003Co-Authors: Wieland Tyrra, Dieter Naumann, Ingo PantenburgAbstract:Abstract Bis(4-Dimethylaminopyridine) group 12 trifluoroacetates—M(OCOCF 3 ) 2 ·2DMAP (M=Zn, Cd, Hg) were prepared in quantitative yields from the anhydrous metal trifluoroacetates and DMAP. All compounds crystallize in the triclinic space group P 1 (no. 2) with two molecules per unit cell. While Zn(OCOCF 3 ) 2 ·2DMAP is built up by well-separated tetrahedral units exhibiting strongly covalent ZnO bonds to monodentate trifluoroactate groups, Cd(OCOCF 3 ) 2 ·2DMAP and Hg(OCOCF 3 ) 2 ·2DMAP form dimeric units. The metal centers are distorted octahedrally surrounded by two axial DMAP ligands, two ionic bridging and one chelating trifluoroacetate group.
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Syntheses and crystal structures of bis(4-Dimethylaminopyridine) group 12 trifluoroacetates — M(OCOCF3)2·2DMAP (M=Zn, Cd, Hg)
Journal of Fluorine Chemistry, 2003Co-Authors: Wieland Tyrra, Dieter Naumann, Ingo PantenburgAbstract:Abstract Bis(4-Dimethylaminopyridine) group 12 trifluoroacetates—M(OCOCF 3 ) 2 ·2DMAP (M=Zn, Cd, Hg) were prepared in quantitative yields from the anhydrous metal trifluoroacetates and DMAP. All compounds crystallize in the triclinic space group P 1 (no. 2) with two molecules per unit cell. While Zn(OCOCF 3 ) 2 ·2DMAP is built up by well-separated tetrahedral units exhibiting strongly covalent ZnO bonds to monodentate trifluoroactate groups, Cd(OCOCF 3 ) 2 ·2DMAP and Hg(OCOCF 3 ) 2 ·2DMAP form dimeric units. The metal centers are distorted octahedrally surrounded by two axial DMAP ligands, two ionic bridging and one chelating trifluoroacetate group.
Vincent Levacher - One of the best experts on this subject based on the ideXlab platform.
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efficient c 3 functionalization of 4 Dimethylaminopyridine dmap a straightforward access to new chiral nucleophilic catalysts
Tetrahedron Letters, 2012Co-Authors: Thomas Poisson, Sylvain Oudeyer, Vincent LevacherAbstract:Abstract Herein, the straightforward C-3 functionalization of 4-Dimethylaminopyridine (DMAP) backbone is disclosed. An efficient halogen-metal exchange procedure from 3-bromo DMAP 1 is reported providing a large panel of C-3 functionalized DMAPs. In addition, a Pd-catalysed C–N cross-coupling reaction is also described furnishing new 3-amino DMAPs. These new functionalization pathways led to the resolution-free synthesis of three new chiral DMAP catalysts in few steps and a good overall yield. These new catalysts were evaluated into the Steglich rearrangement giving modest enantioselectivities (up to 20% ee).
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Efficient C-3 functionalization of 4-Dimethylaminopyridine (DMAP). A straightforward access to new chiral nucleophilic catalysts
Tetrahedron Letters, 2012Co-Authors: Thomas Poisson, Sylvain Oudeyer, Vincent LevacherAbstract:International audienceHerein, the straightforward C-3 functionalization of 4-Dimethylaminopyridine (DMAP) backbone is disclosed. An efficient halogen-metal exchange procedure from 3-bromo DMAP is reported providing a large panel of C-3 functionalized DMAPs. In addn., a Pd-catalyzed C-N cross-coupling reaction is also described furnishing new 3-amino DMAPs. These new functionalization pathways led to the resoln.-free synthesis of three new chiral DMAP catalysts in few steps and a good overall yield. These new catalysts were evaluated in the Steglich rearrangement giving modest enantioselectivities (up to 20% ee)
Seiji Suga - One of the best experts on this subject based on the ideXlab platform.
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Desymmetrization of meso-1,2-Diols by a Chiral N,N-4-Dimethylaminopyridine Derivative Containing a 1,1'-Binaphthyl Unit: Importance of the Hydroxy Groups.
The Journal of organic chemistry, 2017Co-Authors: Hiroki Mandai, Kazuki Fujii, Koichi Mitsudo, Hiroshi Yasuhara, Yukihito Shimomura, Seiji SugaAbstract:We developed an acylative desymmetrization of meso-1,2-diols using a binaphthyl-based N,N-4-Dimethylaminopyridine (DMAP) derivative 1h with tert-alcohol substituents. The reaction proceeds with a wide range of acyclic meso-1,2-diols and six-membered-ring meso-1,2-diols to provide a monoacylate selectively with a high enantiomeric ratio (er). Only 0.1 mol % of the catalyst facilitated the reaction within a short reaction time (3 h) to afford enantio-enriched monoacylated products in moderate to good yield. Several control experiments revealed that the tert-alcohol units of catalyst 1h play a significant role in achieving high catalytic activity, chemoselectivity of monoacylation, and enantioselectivity.
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Kinetic Resolution of Secondary Carbinols by a Chiral N,N-4-Dimethylaminopyridine Derivative Containing a 1,1′-Binaphthyl Unit: Hydrogen Bonding Affects Catalytic Activity and Enantioselectivity
Bulletin of the Chemical Society of Japan, 2016Co-Authors: Kazuki Fujii, Koichi Mitsudo, Hiroki Mandai, Seiji SugaAbstract:We developed an acylative kinetic resolution of secondary carbinols using a binaphthyl-based N,N-4-Dimethylaminopyridine (DMAP) derivative 1d with tert-alcohol substituents. The reaction proceeded with a wide range of carbinols with moderate to high selectivity (s) (up to s = 79.5). Kinetic studies revealed that catalyst 1d was more catalytically active than the corresponding bis-methyl ether 1d′ or DMAP. Hydrogen bonding between tert-alcohols of the catalyst and secondary carbinols was responsible for the enhanced reaction rate and high enantioselectivity.
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kinetic resolution of secondary carbinols by a chiral n n 4 Dimethylaminopyridine derivative containing a 1 1 binaphthyl unit hydrogen bonding affects catalytic activity and enantioselectivity
Bulletin of the Chemical Society of Japan, 2016Co-Authors: Kazuki Fujii, Koichi Mitsudo, Hiroki Mandai, Seiji SugaAbstract:We developed an acylative kinetic resolution of secondary carbinols using a binaphthyl-based N,N-4-Dimethylaminopyridine (DMAP) derivative 1d with tert-alcohol substituents. The reaction proceeded with a wide range of carbinols with moderate to high selectivity (s) (up to s = 79.5). Kinetic studies revealed that catalyst 1d was more catalytically active than the corresponding bis-methyl ether 1d′ or DMAP. Hydrogen bonding between tert-alcohols of the catalyst and secondary carbinols was responsible for the enhanced reaction rate and high enantioselectivity.
