The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Li Liu - One of the best experts on this subject based on the ideXlab platform.
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Highly enantioselective [3 + 2]-annulation of isatin-derived morita-baylis-hillman adducts with cyclic sulfonimines.
Organic letters, 2015Co-Authors: Feng Wei, Hong-yan Huang, Neng-jun Zhong, Dong Wang, Li LiuAbstract:An organocatalytic [3 + 2]-annulation between isatin-derived Morita–Baylis–Hillman adducts and cyclic sulfonimines has been developed in high yields with excellent enantio- and diastereoselectivities via an allylic Nitrogen-Ylide intermediate. The reaction provides access to heavily substituted aza-spirooxindole derivatives, which also contain ring fused cyclic sultams.
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Highly Enantioselective [3 + 2]-Annulation of Isatin-Derived Morita–Baylis–Hillman Adducts with Cyclic Sulfonimines
2015Co-Authors: Feng Wei, Hong-yan Huang, Neng-jun Zhong, Dong Wang, Li LiuAbstract:An organocatalytic [3 + 2]-annulation between isatin-derived Morita–Baylis–Hillman adducts and cyclic sulfonimines has been developed in high yields with excellent enantio- and diastereoselectivities via an allylic Nitrogen-Ylide intermediate. The reaction provides access to heavily substituted aza-spirooxindole derivatives, which also contain ring fused cyclic sultams
Albert Padwa - One of the best experts on this subject based on the ideXlab platform.
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Polycyclic Ring Formation Using Bis-diazolactams for Cascade Stitching
The Journal of organic chemistry, 2016Co-Authors: Sara A. Bonderoff, Albert PadwaAbstract:The chemoselective reaction of donor/acceptor (D/A) and acceptor/acceptor (A/A) diazo moieties in the same molecule was examined using 3-diazo-1-(ethyl 2-diazomalonyl)indolin-2-one under rhodium(II) catalysis. The metallo carbenoid derived from the D/A diazo group is preferentially formed and undergoes selective CH, NH, and OH insertion reactions, cyclopropanation, cyclopropenation, sulfur Ylide formation/2,3-sigmatropic rearrangement, as well as Nitrogen Ylide formation followed by azetidine ring expansion. The initial reaction can be paired with a subsequent tandem cascade sequence involving dipole formation/cycloaddition in either an intra- or intermolecular sense to generate polycyclic N-heterocycles in one pot, with the formation up to three new rings in a single operation. Excellent diastereoselectivity was observed in the intramolecular cycloaddition reaction producing 5 to 7-membered rings.
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Polycyclic Ring Formation Using Bis-diazolactams for Cascade Stitching
2016Co-Authors: Sara A. Bonderoff, Albert PadwaAbstract:The chemoselective reaction of donor/acceptor (D/A) and acceptor/acceptor (A/A) diazo moieties in the same molecule was examined using 3-diazo-1-(ethyl 2-diazomalonyl)indolin-2-one under rhodium(II) catalysis. The metallo carbenoid derived from the D/A diazo group is preferentially formed and undergoes selective CH, NH, and OH insertion reactions, cyclopropanation, cyclopropenation, sulfur Ylide formation/2,3-sigmatropic rearrangement, as well as Nitrogen Ylide formation followed by azetidine ring expansion. The initial reaction can be paired with a subsequent tandem cascade sequence involving dipole formation/cycloaddition in either an intra- or intermolecular sense to generate polycyclic N-heterocycles in one pot, with the formation up to three new rings in a single operation. Excellent diastereoselectivity was observed in the intramolecular cycloaddition reaction producing 5 to 7-membered rings
Javier Pérez-castells - One of the best experts on this subject based on the ideXlab platform.
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Unusual Skeletal Rearrangement of Unsaturated Seven-Membered Lactams into Fused Pyrrolidinolactones
European Journal of Organic Chemistry, 2013Co-Authors: Silvia Alvarez, Ana Gradillas, Gema Domínguez, Javier Pérez-castellsAbstract:Unsaturated ϵ-lactams undergo a novel process involving a skeletal reorganization to give fused pyrrolidine-lactones by reaction with aromatic α-bromo ketones in the presence of 1,4-diazabicyclo[2.2.2]octane and a base. The process involves the formation of an ammonium salt and subsequently a Nitrogen Ylide, which initiates the rearrangement reaction. This species reduces undesired side-reactions such as double-bond shifts or Morita–Baylis–Hilman-type processes. The resulting products are structurally related to kainoids and the transformation of the lactone moiety in the rearranged product paves the way to the synthesis of these potentially bioactive natural products and their derivatives.
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Nitrogen Ylide-mediated cyclopropanation of lactams and lactones
Tetrahedron Letters, 2010Co-Authors: Irene Suarez Del Villar, Ana Gradillas, Gema Domínguez, Javier Pérez-castellsAbstract:Abstract Cyclopropanation of α,β-unsaturated δ-lactams and δ-lactones mediated by Nitrogen Ylides is described. The process tolerates different alkyl halides and gives efficiently bicyclo[4.1.0]heptanes in a totally stereoselective manner. On the other hand, e-lactams under our experimental conditions suffer a novel process involving a skeletal reorganization to give a bicyclic[3.3.0] system.
Feng Wei - One of the best experts on this subject based on the ideXlab platform.
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Highly enantioselective [3 + 2]-annulation of isatin-derived morita-baylis-hillman adducts with cyclic sulfonimines.
Organic letters, 2015Co-Authors: Feng Wei, Hong-yan Huang, Neng-jun Zhong, Dong Wang, Li LiuAbstract:An organocatalytic [3 + 2]-annulation between isatin-derived Morita–Baylis–Hillman adducts and cyclic sulfonimines has been developed in high yields with excellent enantio- and diastereoselectivities via an allylic Nitrogen-Ylide intermediate. The reaction provides access to heavily substituted aza-spirooxindole derivatives, which also contain ring fused cyclic sultams.
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Highly Enantioselective [3 + 2]-Annulation of Isatin-Derived Morita–Baylis–Hillman Adducts with Cyclic Sulfonimines
2015Co-Authors: Feng Wei, Hong-yan Huang, Neng-jun Zhong, Dong Wang, Li LiuAbstract:An organocatalytic [3 + 2]-annulation between isatin-derived Morita–Baylis–Hillman adducts and cyclic sulfonimines has been developed in high yields with excellent enantio- and diastereoselectivities via an allylic Nitrogen-Ylide intermediate. The reaction provides access to heavily substituted aza-spirooxindole derivatives, which also contain ring fused cyclic sultams
Sara A. Bonderoff - One of the best experts on this subject based on the ideXlab platform.
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Polycyclic Ring Formation Using Bis-diazolactams for Cascade Stitching
The Journal of organic chemistry, 2016Co-Authors: Sara A. Bonderoff, Albert PadwaAbstract:The chemoselective reaction of donor/acceptor (D/A) and acceptor/acceptor (A/A) diazo moieties in the same molecule was examined using 3-diazo-1-(ethyl 2-diazomalonyl)indolin-2-one under rhodium(II) catalysis. The metallo carbenoid derived from the D/A diazo group is preferentially formed and undergoes selective CH, NH, and OH insertion reactions, cyclopropanation, cyclopropenation, sulfur Ylide formation/2,3-sigmatropic rearrangement, as well as Nitrogen Ylide formation followed by azetidine ring expansion. The initial reaction can be paired with a subsequent tandem cascade sequence involving dipole formation/cycloaddition in either an intra- or intermolecular sense to generate polycyclic N-heterocycles in one pot, with the formation up to three new rings in a single operation. Excellent diastereoselectivity was observed in the intramolecular cycloaddition reaction producing 5 to 7-membered rings.
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Polycyclic Ring Formation Using Bis-diazolactams for Cascade Stitching
2016Co-Authors: Sara A. Bonderoff, Albert PadwaAbstract:The chemoselective reaction of donor/acceptor (D/A) and acceptor/acceptor (A/A) diazo moieties in the same molecule was examined using 3-diazo-1-(ethyl 2-diazomalonyl)indolin-2-one under rhodium(II) catalysis. The metallo carbenoid derived from the D/A diazo group is preferentially formed and undergoes selective CH, NH, and OH insertion reactions, cyclopropanation, cyclopropenation, sulfur Ylide formation/2,3-sigmatropic rearrangement, as well as Nitrogen Ylide formation followed by azetidine ring expansion. The initial reaction can be paired with a subsequent tandem cascade sequence involving dipole formation/cycloaddition in either an intra- or intermolecular sense to generate polycyclic N-heterocycles in one pot, with the formation up to three new rings in a single operation. Excellent diastereoselectivity was observed in the intramolecular cycloaddition reaction producing 5 to 7-membered rings