5461-49-4Relevant articles and documents
Isomorphism of chiral ammonium salts Ph(All)N+Et(Me)X-·CHCl3
Kostyanovsky, Remir G.,Lyssenko, Konstantin A.,Krutius, Oleg N.,Kostyanovsky, Vasily R.
, p. 19 - 20 (2009)
The title ammonium salts (X = Br, I) were synthesized, the identity of crystal structures for them (space groups P212121, Z = 4) was found, spontaneous resolution of Ph(All)N+Et(Me)Br-·CHCl3 was performed, and the impossibility of replacement of the solvate molecule by CHBr3 or CH2Hal2 (Hal = Cl, Br, I) was demonstrated by 1H NMR and X-ray diffraction studies.
Method for exciting C-C bond fracture acylation and application
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Paragraph 0034-0042; 0205-0213, (2021/07/21)
The invention provides a method for exciting C-C bond breakage acylation and application; the method comprises the following steps: mixing a compound with a structural formula shown in the specification with an organic solvent, and reacting in oxygen and
A substituent- And temperature-controllable NHC-derived zwitterionic catalyst enables CO2upgrading for high-efficiency construction of formamides and benzimidazoles
Li, Hu,Li, Zhengyi,Wu, Hongguo,Yang, Song,Yu, Zhaozhuo,Zhang, Lilong,Zhu, Kaixun
supporting information, p. 5759 - 5765 (2021/08/23)
Chemocatalytic upgrading of the greenhouse gas CO2 to valuable chemicals and biofuels has attracted broad attention in recent years. Among the reported approaches, N-formylation of CO2 with an amine is of great significance due to its versatility in the construction of N-containing linear and cyclic skeletons. Herein, a stable N-heterocyclic carbene-carboxyl adduct (NHC-CO2) was facilely prepared and could be used as a recyclable zwitterionic catalyst for efficient CO2 reductive upgrading via either N-formylation or further coupling with cyclization under mild conditions (25 °C, 1 atm CO2) using hydrosilane as a hydrogen source. More than 30 different alkyl and aromatic amines could be transformed into the corresponding formamides or benzimidazoles with remarkable yields (74%-98%). The electronic effect of the introduced substituent on NHC-CO2 was found to evidently affect the thermostability and nucleophilicity of the zwitterionic catalyst, which is directly correlated with its catalytic activity. Moreover, NHC-CO2 could supply CO2 by in situ decarboxylation at a specific temperature that is dependent on the introduced substituent type. Experimental and computational studies showed that the carboxyl species on NHC-CO2 was not only a nucleophilic center, but also a C1 source which rapidly captures or substitutes ambient CO2 during hydrosilylation. In addition, a simple and green conceptual process was designed for the product purification and catalyst recycling, with a good feasibility for small-scale production.
