3009-97-0Relevant articles and documents
Iron-catalyzed reductive strecker reaction
Yan, Fachao,Huang, Zijun,Du, Chen-Xia,Bai, Jian-Fei,Li, Yuehui
, p. 188 - 194 (2021/02/03)
Strecker reaction is widely applied for the synthesis of amino acids from aldehydes, amines and cyanides. Herein, we report the FeI2-catalyzed reductive Strecker type reaction of formamides instead of aldehydes to produce amino acetonitriles. The challenging capture of carbinolamine intermediates by CN? was achieved via Fe catalysis. This approach afforded better yields than the use of Ir- or Rh-catalysts. The application ability of this methodology is demonstrated by 1) one-pot construction of (13C labeled) complex molecules from CO2 via amino acetonitrile intermediates and 2) convenient production of homologated carboxylic acids from aldehydes.
Dynamics in Catalytic Asymmetric Diastereoconvergent (3 + 2) Cycloadditions with Isomerizable Nitrones and α-Keto Ester Enolates
Adachi, Masaya,Akakabe, Mai,Ezawa, Tetsuya,Hashizume, Daisuke,Koshino, Hiroyuki,Sodeoka, Mikiko,Sohtome, Yoshihiro
supporting information, p. 9094 - 9104 (2021/07/01)
Reaction design in asymmetric catalysis has traditionally been predicated on a structurally robust scaffold in both substrates and catalysts, to reduce the number of possible diastereomeric transition states. Herein, we present the stereochemical dynamics in the Ni(II)-catalyzed diastereoconvergent (3 + 2) cycloadditions of isomerizable nitrile-conjugated nitrones with α-keto ester enolates. Even in the presence of multiple equilibrating species, the catalytic protocol displays a wide substrate scope to access a range of CN-containing building blocks bearing adjacent stereocenters with high enantio- and diastereoselectivities. Our computational investigations suggest that the enantioselectivity is governed in the deprotonation process to form (Z)-Ni-enolates, while the unique syn addition is mainly controlled by weak noncovalent bonding interactions between the nitrone and ligand.
Covalently hooked EOSIN-Y in a Zr(IV) framework as visible-light mediated, heterogeneous photocatalyst for efficient C–H functionalization of tertiary amines
Kumar, Gaurav,Solanki, Pratik,Nazish, Mohd,Neogi, Subhadip,Kureshy, Rukhsana I.,Khan, Noor-ul H.
, p. 298 - 304 (2019/02/26)
Herein, we report the synthesis of a novel heterogeneous photo-catalyst by utilizing post-synthetic modification of an amine functionalized Zr(IV) metal-organic framework (UiO-66-NH2) through covalent hooking of EOSIN-Y via dehydrating coupling. The characterization of the catalyst was accomplished by FT-IR, XRD, BET surface analysis, TGA, as well as TEM, SEM, XPS, DRS-UV–visible, and NMR spectroscopy, confirming successful covalent linking of EOSIN-Y with the pendent –NH2 functionality in the framework. That post-modified EY@UiO-66-NH2 acts as simple and green visible light mediated photo-catalyst for the C–H activation of tertiary amines with excellent yields. Importantly, the activity of dye incorporated heterogeneous photo-catalyst is found superior to that for the homogeneous photo-catalyst EOSIN-Y. Thus, separation difficulty of homogeneous catalysis, as well as the environmental adverse effects of toxic EOSIN-Y can be excluded by developing such photo-catalyst. Moreover, EY@UiO-66-NH2 catalyst could be consistently recycled up to 10 cycles, without any significant loss in activity. Based on literature report and experimental findings, we also propose a plausible mechanism for the reaction.
