95-21-6Relevant articles and documents
Disubstituted Ferrocenyl Iodo- And Chalcogenoalkynes as Chiral Halogen and Chalcogen Bond Donors
Aubert, Emmanuel,Cossu, Sergio,Mamane, Victor,Pale, Patrick,Peluso, Paola,Weiss, Robin,Wenger, Emmanuel
, p. 3936 - 3950 (2020)
Asymmetric catalysis based on halogen and chalcogen bonds (XB and ChB) is in its infancy, and the search for new chiral XB and ChB donors represents a crucial step toward its development. In this context, we designed and prepared new motifs containing three key substructures: namely, regions of electron charge density depletion centered on iodine and chalcogen atoms, the ethynyl functionality, and the planar chiral ferrocenyl platform. Nine ferrocenyl iodoalkynes were prepared as pure enantiomers by asymmetric synthesis. The XB donor property of racemic ferrocenyl iodoalkynes was demonstrated in solution in two benchmark reactions: the Ritter reaction and the benzoxazole synthesis from thioamides. In contrast, the ferrocenyl chalcogenoalkynes were far less active in these reactions. The potential of racemic and enantiopure ferrocenyl iodoalkynes as XB donors was also confirmed by X-ray diffraction analysis, showing I···C contacts between the electropositive σ-hole of the iodine atom and electron-rich πclouds for all crystal structures studied in the solid state.
Synthetic Applications of a New Magnetic Mesoporous Nanocomposite Catalyst Fe3O4@MCM-41@NH-SO3H
Pourhasan-Kisomi, Reyhaneh,Shirini, Farhad,Golshekan, Mostafa
, p. 166 - 175 (2021/04/09)
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Acid-promoted cleavage of the C–C double bond of N-(2-Hydroxylphenyl)enaminones for the synthesis of benzoxazoles
Ge, Bailu,Peng, Yanling,Liu, Jing,Wen, Si,Peng, Cheng,Cheng, Guolin
, (2019/12/09)
An acid-mediated selective cleavage of C–C double bond of N-(2-hydroxylphenyl)enaminones with formation a new C–O bond for the synthesis of 2-substituted benzoxazoles has been developed. This protocol proceeds under transition metal- and oxidant-free conditions with broad functional group tolerance. The oxidative cleavage of C–C double bond of N-(2-hydroxylphenyl)enaminone is also realized using NCS or NFSI as oxidants with release of 2,2-dihalogen-acetophenone fragments.