10335-79-2Relevant articles and documents
Silver-Catalyzed Acyl Nitrene Transfer Reactions Involving Dioxazolones: Direct Assembly of N-Acylureas
Yang, Zheng-Lin,Xu, Xin-Liang,Chen, Xue-Rong,Mao, Zhi-Feng,Zhou, Yi-Feng
supporting information, p. 648 - 652 (2020/12/21)
Dioxazolones and isocyanides are useful synthetic building blocks, and have attracted significant attention from researchers. However, the silver-catalyzed nitrene transfer reaction of dioxazolones has not been investigated to date. Herein, a silver-catalyzed acyl nitrene transfer reaction involving dioxazolones, isocyanides, and water was realized in the presence of Ag2O to afford a series of N-acylureas in moderate to good yields.
Palladium-Catalyzed 5-exo-dig Cyclization Cascade, Sequential Amination/Etherification for Stereoselective Construction of 3-Methyleneindolinones
Zuo, Youpeng,He, Xinwei,Tang, Qiang,Hu, Wangcheng,Zhou, Tongtong,Hu, Wenbo,Shang, Yongjia
, p. 2117 - 2123 (2020/12/22)
An cascade intramolecular 5-exo-dig cyclization of N-(2-iodophenyl)propiolamides and sequential amination/etherification (with N-hydroxybenzamides, phenyl hydroxycarbamate) protocol for the synthesis of amino- and phenoxy-substituted 3-methyleneindolinones using unexpensive Pd(PPh3)4 as catalyst has been developed. The protocol enables the assembly of structurally important oxindole cores featuring moderate functional group tolerance (particularly the halo group), affording a broad spectrum of products with diverse substituents in good to excellent yields. (Figure presented.).
Direct synthesis of benzoxazinones via Cp*Co(III)-catalyzed C–H activation and annulation of sulfoxonium ylides with dioxazolones
Yu, Yongqi,Xia, Zhen,Wu, Qianlong,Liu, Da,Yu, Lin,Xiao, Yuanjiu,Tan, Ze,Deng, Wei,Zhu, Gangguo
supporting information, p. 1263 - 1266 (2020/10/08)
A highly novel and direct synthesis of benzoxazinones was developed via Cp*Co(III)-catalyzed C–H activation and [3 + 3] annulation between sulfoxonium ylides and dioxazolones. The reaction is conducted under base-free conditions and tolerates various functional groups. Starting from diverse readily available sulfoxonium ylides and dioxazolones, a variety of benzoxazinones could be synthesized in one step in 32%-75% yields.
Synthesis of sulfimides and N-Allyl-N-(thio)amides by Ru(II)catalyzed nitrene transfer reactions of N-acyloxyamides
Zhang, Xinyu,Lin, Bo,Chen, Jianhui,Chen, Jiajia,Luo, Yanshu,Xia, Yuanzhi
supporting information, p. 819 - 825 (2021/02/01)
The N-acyloxyamides were employed as effective N-acyl nitrene precursors in reactions with thioethers under the catalysis of a commercially available Ru(II) complex, from which a variety of sulfimides were synthesized efficiently and mildly. If an allyl group is contained in the thioether precursor, the [2,3]-sigmatropic rearrangement of the sulfimide occurs simultaneously and the N-allyl-N-(thio)amides were obtained as the final products. Preliminary mechanistic studies indicated that the Ru-nitrenoid species should be a key intermediate in the transformation.
Palladium-catalyzed cascade decarboxylative amination/6- endo-dig benzannulation of o-alkynylarylketones with n-hydroxyamides to access diverse 1-naphthylamine derivatives
Zuo, Youpeng,He, Xinwei,Tang, Qiang,Hu, Wangcheng,Zhou, Tongtong,Shang, Yongjia
, p. 3890 - 3894 (2020/05/18)
An efficient and practical one-pot strategy to produce highly substituted 1-naphthylamines via sequential palladium-catalyzed decarboxylative amination/intramolecular 6-endo-dig benzannulation reactions has been described. In this reaction, a broad range of electron-rich, electron-neutral, and electron-deficient o-alkynylarylketones react well with N-hydroxyl aryl/alkylamides to give a diversity of 1-naphthylamines in good to excellent yields under mild reaction conditions. The gram-scale synthesis, with benefits such as undiminished product yield and easy transformation, illustrated the practicality of this method.
Divergent Synthesis of Tunable Cyclopentadienyl Ligands and Their Application in Rh-Catalyzed Enantioselective Synthesis of Isoindolinone
Cui, Wen-Jun,Wu, Zhi-Jie,Gu, Qing,You, Shu-Li
, p. 7379 - 7385 (2020/08/19)
A series of rhodium complexes bearing sterically and electronically tunable cyclopentadienyl ligands, prepared by utilizing Co2(CO)8-mediated [2+2+1] cyclization as a key step, were synthesized. In the presence of 2.5 mol% of CpmRh4, unprecedented enantioselective [4+1] annulation reaction of benzamides and alkenes was achieved with a broad substrate scope under mild reaction conditions, providing a variety of isoindolinones with excellent regio-and enantioselectivity (up to 94% yield, 97:3 er). Preliminary mechanistic studies suggest that the reaction involves an oxidative Heck reaction and an intramolecular enantioselective alkene hydroamination reaction.
RhIII-Catalyzed C?H Activation of Aryl Hydroxamates for the Synthesis of Isoindolinones
Shaaban, Saad,Davies, Caitlin,Merten, Christian,Flegel, Jana,Otte, Felix,Strohmann, Carsten,Waldmann, Herbert
supporting information, p. 10729 - 10734 (2020/07/25)
RhIII-catalyzed C?H functionalization reaction yielding isoindolinones from aryl hydroxamates and ortho-substituted styrenes is reported. The reaction proceeds smoothly under mild conditions at room temperature, and tolerates a range of functional groups. Experimental and computational investigations support that the high regioselectivity observed for these substrates results from the presence of an ortho-substituent embedded in the styrene. The resulting isoindolinones are valuable building blocks for the synthesis of bioactive compounds. They provide easy access to the natural-product-like compounds, isoindolobenzazepines, in a one-pot two-step reaction. Selected isoindolinones inhibited Hedgehog (Hh)-dependent differentiation of multipotent murine mesenchymal progenitor stem cells into osteoblasts.
Dioxazolones as masked ester surrogates in the Pd(ii)-catalyzed direct C-H arylation of 6,5-fused heterocycles
Saxena, Paridhi,Maida, Neha,Kapur, Manmohan
supporting information, p. 11187 - 11190 (2019/09/30)
A simple and effective Pd(ii)-catalyzed regioselective C(2)-H arylation of 6,5-fused heterocycles with dioxazolones as a masked ester surrogate under mild conditions is reported. The significance of the arylation is highlighted by the new reactivity demonstrated in dioxazolones via proximal C-H activation of the cyclic carbonate of the hydroxamic acid functionality under protic conditions.
Consecutive Lossen rearrangement/transamidation reaction of hydroxamic acids under catalyst- and additive-free conditions
Jia, Mengmeng,Zhang, Heng,Lin, Yongjia,Chen, Dimei,Chen, Yanmei,Xia, Yuanzhi
, p. 3615 - 3624 (2018/05/26)
The Lossen rearrangement is a classic process for transforming activated hydroxamic acids into isocyanate under basic or thermal conditions. In the current report we disclosed a consecutive Lossen rearrangement/transamidation reaction in which unactivated hydroxamic acids were converted into N-substituted formamides in a one-pot manner under catalyst- and additive-free conditions. One feature of this novel transformation is that the formamide plays triple roles in the reaction by acting as a readily available solvent, a promoter for additive-free Lossen rearrangement, and a source of the formyl group in the final products. Acyl groups other than formyl could also be introduced into the product when changing the solvent to other low molecular weight aliphatic amide derivatives. The solvent-promoted Lossen rearrangement was better understood by DFT calculations, and the intermediacy of isocyanate and amine was supported well by experiments, in which the desired products were obtained in excellent yields under similar conditions. Not only monosubstituted formamides were synthesized from hydroxamic acids, but also N,N-disubstituted formamides were obtained when secondary amines were used as precursors.
Experimental and computational studies on H2O-promoted, Rh-catalyzed transient-ligand-free ortho-C(sp2)-H amidation of benzaldehydes with dioxazolones
Ding, Jun,Jiang, Wei,Bai, He-Yuan,Ding, Tong-Mei,Gao, Dafang,Bao, Xiaoguang,Zhang, Shu-Yu
supporting information, p. 8889 - 8892 (2018/08/17)
An efficient and convenient ligand-free, rhodium-catalyzed ortho-C(sp2)-H amidation of benzaldehydes with dioxazolones using H2O as the key promoter is described. Using this protocol, a wide range of benzaldehyde substrates were selectively amidated in good to excellent yields with broad functional group compatibility. KIE experiments revealed that the C-H bond activation was likely the rate-limiting step. In addition, computational studies indicated that the catalyst precursor interacted with water and dioxazolones to generate the active catalytic species. Notably, the practicality and efficacy of this method were illustrated by a late-stage amidation of an estrone-derived molecule and further transformations of the amidated product.
