273-53-0Relevant articles and documents
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Kozlov,N.S.,Kiselev,B.I.
, (1966)
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Photocyclization of o-Nitrophenyl Alkyl Ethers
Oguchi, Shoshichi,Torizuka, Hiroshi
, p. 2425 (1980)
o-Nitrophenyl alkyl ethers 1a, 1b, and 1c undergo photocyclization to give benzoxazoles 2a, 2b, and 2c, respectively.
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Grellmann,Taner
, p. 375,376 (1974)
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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.
Synthesis of isocyanides by reacting primary amines with difluorocarbene
Si, Yi-Xin,Zhu, Peng-Fei,Zhang, Song-Lin
supporting information, p. 9086 - 9090 (2020/11/30)
A general, convenient, and friendly route for preparing a versatile building block of isocyanides from primary amines is developed. Difluorocarbene, generated in situ from decarboxylation of chlorodifluoroacetate, reacts efficiently with primary amines to produce isocyanides. Various primary amines are well tolerated, including aryl, heteroaryl, benzyl, and alkyl amines, as well as amine residues in amino acids and peptides. Late-stage functionalization of biologically active amines is demonstrated, showing its practical capacity in drug design and peptide modification.
Application of [PVP-SO3H] HSO4 as an Efficient Polymeric-Based Solid Acid Catalyst in the Synthesis of Some Benzimidazole Derivatives
Roudsari, Fatemeh Pakpour,Seddighi, Mohadeseh,Shirini, Farhad,Tajik, Hassan
, p. 1 - 14 (2020/07/27)
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