13213-36-0Relevant articles and documents
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Hey
, p. 18,20 (1930)
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Copper-Catalyzed Aza-Sonogashira Cross-Coupling To Form Ynimines: Development and Application to the Synthesis of Heterocycles
Lavernhe, Rémi,Torres-Ochoa, Rubén O.,Wang, Qian,Zhu, Jieping
supporting information, p. 24028 - 24033 (2021/10/07)
Nitrogen-substituted alkynes, such as ynamines and ynamides, are versatile synthetic building blocks. Ynimines bearing additional nucleophilic and electrophilic centers relative to ynamines and ynamides are expected to have high synthetic potential. However, their chemical reactivity remains unexplored owing mainly to the lack of synthetic accessibility. We report herein a versatile copper-catalyzed synthesis of ynimines from readily available O-acetyl ketoximes and terminal alkynes. A wide range of O-acetyl ketoximes derived from diaryl ketones, aryl alkyl ketones and dialkyl ketones underwent cross-coupling with a diverse set of terminal alkynes to afford the ynimines in good to excellent yields. An unprecedented [5+1] heteroannulation reaction exploiting the reactivity of the ynimine generated in situ was subsequently developed for the synthesis of medicinally important heterocycles, including isoquinolines, azaindoles, azabenzofurans, azabenzothiophenes and carbolines.
Iridium-catalyzed highly chemoselective and efficient reduction of nitroalkenes to nitroalkanes in water
Chen, Yang,Liu, Changmeng,Xu, Dong,Xu, Jiaxi,Yang, Zhanhui
, p. 6050 - 6058 (2021/08/23)
An iridium-catalyzed highly chemoselective and efficient transfer hydrogenation reduction of structurally diverse nitroalkenes was realized at very low catalyst loading (S/C = up to 10000 or 20?000), using formic acid or sodium formate as a traceless hydride donor in water. Excellent functionality tolerance is also observed. The turnover number and turnover frequency of the catalyst reach as high as 18?600 and 19?200 h-1, respectively. An inert atmosphere protection is not required. The reactivities of nitroalkenes are dependent on their substitution pattern, and the pH value is a key factor to accomplish the complete conversion and excellent chemoselectivity. Purification of products is achieved by simple extraction without column chromatography. The reduction procedure is facilely amplified to 10 g scale at 10?000 S/C ratio. The potential of this green reduction in enantioselective hydrogenation has been demonstrated.