27374-00-1Relevant articles and documents
Copper-free Sandmeyer-type Reaction for the Synthesis of Sulfonyl Fluorides
Zhong, Tao,Pang, Meng-Ke,Chen, Zhi-Da,Zhang, Bin,Weng, Jiang,Lu, Gui
supporting information, p. 3072 - 3078 (2020/04/10)
A copper-free Sandmeyer-type fluorosulfonylation reaction is reported. Utilizing Na2S2O5 and Selectfluor as the sulfur dioxide and fluorine sources, respectively, aryldiazonium salts were transformed into sulfonyl fluorides. The one-pot direct synthesis of sulfonyl fluorides from aromatic amines was also realized via in situ diazotization. The practicality of this method was demonstrated by the broad functional group tolerance, gram-scale synthesis, and late-stage fluorosulfonylation of natural products and pharmaceuticals.
Systematic Evaluation of 2-Arylazocarboxylates and 2-Arylazocarboxamides as Mitsunobu Reagents
Hirose, Daisuke,Gazvoda, Martin,Ko?mrlj, Janez,Taniguchi, Tsuyoshi
, p. 4712 - 4729 (2018/04/26)
2-Arylazocarboxylate and 2-arylazocarboxamide derivatives can serve as replacements of typical Mitsunobu reagents such as diethyl azodicarboxylate. A systematic investigation of the reactivity and physical properties of those azo compounds has revealed that they have an excellent ability as Mitsunobu reagents. These reagents show similar or superior reactivity as compared to the known azo reagents and are applicable to the broad scope of substrates. pKa and steric effects of substrates have been investigated, and the limitation of the Mitsunobu reaction can be overcome by choosing suitable reagents from the library of 2-arylazocarboxylate and 2-aryl azocarboxamide derivatives. Convenient recovery of azo reagents is available by one-pot iron-catalyzed aerobic oxidation, for example. SC-DSC analysis of representative 2-arylazocarboxylate and 2-arylazocarboxamide derivatives has shown high thermal stability, indicating that these azo reagents possess lower chemical hazard compared with typical azo reagents.
[Ph3C][B(C6F5)4]: A Highly Efficient Metal-Free Single-Component Initiator for the Helical-Sense-Selective Cationic Copolymerization of Chiral Aryl Isocyanides and Achiral Aryl Isocyanides
Yan, Xinwen,Zhang, Shaowen,Zhang, Pengfei,Wu, Xiaolu,Liu, An,Guo, Ge,Dong, Yuping,Li, Xiaofang
supporting information, p. 8947 - 8952 (2018/07/25)
Commercially available [Ph3C][B(C6F5)4] served as a highly efficient metal-free and single-component initiator not only for the carbocationic polymerization of polar and bulky aryl isocyanides with extremely high activity up to 1.2×107 g of polymer/(molcat. h), but also for the helical-sense-selective polymerization of chiral aryl isocyanides and copolymerization with achiral aryl isocyanides to afford high-molecular-weight functional poly(aryl isocyanide)s with good solubility as well as AIE characteristics and/or a single-handed helical conformation.
Advances and mechanistic insight on the catalytic Mitsunobu reaction using recyclable azo reagents
Hirose, Daisuke,Gazvoda, Martin,Ko?mrlj, Janez,Taniguchi, Tsuyoshi
, p. 5148 - 5159 (2016/07/29)
Ethyl 2-arylhydrazinecarboxylates can work as organocatalysts for Mitsunobu reactions because they provide ethyl 2-arylazocarboxylates through aerobic oxidation with a catalytic amount of iron phthalocyanine. First, ethyl 2-(3,4-dichlorophenyl)hydrazinecarboxylate has been identified as a potent catalyst, and the reactivity of the catalytic Mitsunobu reaction was improved through strict optimization of the reaction conditions. Investigation of the catalytic properties of ethyl 2-arylhydrazinecarboxylates and the corresponding azo forms led us to the discovery of a new catalyst, ethyl 2-(4-cyanophenyl)hydrazinecarboxylates, which expanded the scope of substrates. The mechanistic study of the Mitsunobu reaction with these new reagents strongly suggested the formation of betaine intermediates as in typical Mitsunobu reactions. The use of atmospheric oxygen as a sacrificial oxidative agent along with the iron catalyst is convenient and safe from the viewpoint of green chemistry. In addition, thermal analysis of the developed Mitsunobu reagents supports sufficient thermal stability compared with typical azo reagents such as diethyl azodicarboxylate (DEAD). The catalytic system realizes a substantial improvement of the Mitsunobu reaction and will be applicable to practical synthesis.
Development of a redox-free Mitsunobu reaction exploiting phosphine oxides as precursors to dioxyphosphoranes
Tang, Xiaoping,Chapman, Charlotte,Whiting, Matthew,Denton, Ross
supporting information, p. 7340 - 7343 (2014/07/07)
The development of the first redox-free protocol for the Mitsunobu reaction is described. This has been achieved by exploiting triphenylphosphine oxide-the unwanted by-product in the conventional Mitsunobu reaction-as the precursor to the active P(v) coupling reagent. Multinuclear NMR studies are consistent with hydroxyl activation via an alkoxyphosphonium salt.
Synthesis, antimicrobial evaluation, and QSAR analysis of 2-isopropyl-5-methylcyclohexanol derivatives
Singh, Manjeet,Kumar, Sunil,Kumar, Ashwani,Kumar, Pradeep,Narasimhan, Balasubramanian
, p. 511 - 522 (2012/08/07)
A series of 2-isopropyl-5-methylcyclohexanol derivatives were synthesized and evaluated for their antibacterial activity against Gram-positive Staphylococcus aureus and Bacillus subtilis and Gram-negative Escherichia coli and in vitro antifungal activity against Candida albicans and Aspergillus niger. The results of antimicrobial activity demonstrated that the compounds 10, 20, and 21 were the most active ones among the synthesized compounds. The QSAR studies revealed the importance of dipole moment (μ), total energy (Te), and topological parameters (κ1 and κ3) in describing the antimicrobial activity of 2-isopropyl-5-methylcyclohexanol derivatives. Springer Science+Business Media, LLC 2011.
Alkylation of acylmetalates with alkyl halides to prepare Fischer carbene complexes: An improved protocol
Nandi, Bappaditya,Sinha, Surajit
supporting information; scheme or table, p. 106 - 113 (2011/03/17)
Alkoxy Fischer carbene complexes have been synthesized by alkylation of lithium acylmetalates with alkyl halides in the presence of catalytic amount (5-10 mol %) of n-tetrabutylammonium bromide (n-Bu4NBr) restricting the temperature below 55 °C to minimize decomposition of the product. The reaction occurs in a biphasic condition involving water and alkyl halide. The effect of cesium on this alkylation reaction has been studied. The presence of a radical quencher, di-tert-butyl phenol, neither affects the yield nor leads to the formation of dimer of di-tert-butyl phenol, which rules out the possibility of radical pathway mechanism. The kinetic study and the 1H NMR spectra of products suggest an SN2 pathway particularly involving alkyl halides.
Microwave-assisted ester formation using O-alkylisoureas: A convenient method for the synthesis of esters with inversion of configuration
Chighine, Alessandra,Crosignani, Stefano,Arnal, Marie-Claire,Bradley, Mark,Linclau, Bruno
experimental part, p. 4753 - 4762 (2009/10/17)
(Chemical Equation Presented) The formation of carboxylic esters via reaction of carboxylic acids with O-alkylisoureas proceeds in excellent yields with very short reaction times when conducted in a monomode microwave synthesizer. Efficient processes were
BIS(2-ALKOXYETHYL) AZODICARBOXYLATE ESTER COMPOUND AND INTERMEDIATE FOR PRODUCTION OF THE SAME
-
Page/Page column 17-18, (2009/11/30)
Provided is an industrially safe and useful azodicarboxylic acid bis(2-alkoxyethyl) ester compound that is useful for the Mitsunobu reaction in which it is used in combination with a phosphorus compound to carry out a dehydration condensation reaction, and also useful as an oxidizing agent, and a starting material for various synthetic processes. Also provided are a production intermediate of the above-described compound, and methods for producing these compounds. An azodicarboxylic acid bis(2-alkoxyethyl) ester compound represented by formula (1); wherein A represents an alkyl group having 1 to 10 carbon atoms.
Easily prepared azopyridines as potent and recyclable reagents for facile esterification reactions. An efficient modified mitsunobu reaction
Iranpoor, Nasser,Firouzabadi, Habib,Khalili, Dariush,Motevalli, Somayeh
, p. 4882 - 4887 (2008/09/21)
(Chemical Equation Presented) The 2,2′-, 3,3′-, and 4,4′-azopyridines (azpy) and their alkyl pyridinium ionic liquids were studied as a new class of electron-deficient reagents for Mitsunobu esterification reactions. Among these compounds, 4,4′-azopyridine was found to be the most suitable one for esterification and thioesterification reactions. This new reagent promises to provide general and complementary solutions for separation problems in Mitsunobu reactions without restricting the reaction scope and facilitates the isolation of its hydrazine byproduct. The pyridine hydrazine byproduct can be simply recycled to its azopyridine by an oxidation reaction.