7699-19-6Relevant articles and documents
A Unified Catalytic Asymmetric (4+1) and (5+1) Annulation Strategy to Access Chiral Spirooxindole-Fused Oxacycles
Gao, Min,Gong, Xiangnan,Hu, Lin,Luo, Yanshu,Xia, Yuanzhi,Xu, Qianlan,Zhao, Yukun
, p. 19813 - 19820 (2021/08/03)
A unified catalytic asymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C?C and the subsequent umpolung C?O bond-forming reactions with one-carbon unit nucleophiles, thus providing a distinct method to access the valuable chiral spirooxindole-tetrahydrofurans and -tetrahydropyrans with good yields and high enantioselectivities under mild conditions. DFT calculations were performed to rationalize the origin of high enantioselectivity. The gram-scale syntheses and synthetic utility of the resultant products were also demonstrated.
Selective formation of γ-lactams via C-H amidation enabled by tailored iridium catalysts
Hong, Seung Youn,Park, Yoonsu,Hwang, Yeongyu,Kim, Yeong Bum,Baik, Mu-Hyun,Chang, Sukbok
, p. 1016 - 1021 (2018/03/09)
Intramolecular insertion of met al nitrenes into carbon-hydrogen bonds to form γ-lactam rings has traditionally been hindered by competing isocyanate formation. We report the application of theory and mechanism studies to optimize a class of pentamethylcyclopentadienyl iridium(III) catalysts for suppression of this competing pathway. Modulation of the stereoelectronic properties of the auxiliary bidentate ligands to be more electron-donating was suggested by density functional theory calculations to lower the C-H insertion barrier favoring the desired reaction. These catalysts transform a wide range of 1,4,2-dioxazol-5-ones, carbonylnitrene precursors easily accessible from carboxylic acids, into the corresponding γ-lactams via sp3 and sp2 C-H amidation with exceptional selectivity. The power of this method was further demonstrated by the successful late-stage functionalization of amino acid derivatives and other bioactive molecules.
Synthesis of indolin-2-one, isoindolin-1-one, and indole derivatives from homophthalic acid
Kilikli, Alper A.,Dengiz, Cagatay,Oezcan, Sevil,Balci, Metin
experimental part, p. 3697 - 3705 (2011/12/21)
We hereby report the preparation of indolin-2-one and isoindolin-1-one and their derivatives starting from 2-(carboxymethyl)benzoic acid, which was first regiospecifically converted into the isomeric half esters. Transformation of the acid functionalities to the acyl azides followed by Curtius rearrangement gave the regioisomeric isocyanates. Reaction of the isocyanates with aniline produced urethane derivatives. Intramolecular cyclization provided the target compounds. Georg Thieme Verlag Stuttgart. New York.
