53066-99-2Relevant articles and documents
Minisci aroylation of N-heterocycles using choline persulfate in water under mild conditions
Hunjan, Mandeep Kaur,Laha, Joydev K.,Tinwala, Ummehani
, p. 22853 - 22859 (2021/12/24)
Metal persulfate mediated thermal oxidative organic transformations invariably require a higher temperature and frequently use an organic solvent. The objective of this work was to develop persulfate mediated oxidative transformations that can be performed nearly at room temperature using water as a solvent. This report describes modified Minisci aroylation of isoquinolines with arylglyoxylic acids using choline persulfate and its pre-composition (choline acetate and K2S2O8) in water at 40 °C. A few other nitrogen heterocycles were also utilized affording various aroylated products in good to excellent yields. Unlike metal persulfate that could produce metal salt byproducts, a key feature of the chemistry reported herein includes the use of environmentally benign choline persulfate containing biodegradable choline as a counter-cation, the Minisci reaction demonstrated at 40 °C in water as the only solvent, and unconventional activation of persulfate. This journal is
Aroylation of Electron-Rich Pyrroles under Minisci Reaction Conditions
Laha, Joydev K.,Kaur Hunjan, Mandeep,Hegde, Shalakha,Gupta, Anjali
supporting information, p. 1442 - 1447 (2020/02/22)
The development of Minisci acylation on electron-rich pyrroles under silver-free neutral conditions has been reported featuring the regioselective monoacylation of (NH)-free pyrroles. Unlike conventional Minisci conditions, the avoidance of any acid that could result in the polymerization of pyrroles was the key to success. The umpolung reactivity of the nucleophilic acyl radical, generated in situ from arylglyoxylic acid, could help explain the mechanism of product formation with electron-rich pyrroles. Alternatively, the nucleophilic substitution of the acyl radical on the electron-deficient pyrrole radical cation is proposed.
Three-Component Activation/Alkynylation/Cyclocondensation (AACC) Synthesis of Enhanced Emission Solvatochromic 3-Ethynylquinoxalines
Merkt, Franziska K.,H?wedes, Simon P.,Gers-Panther, Charlotte F.,Gruber, Irina,Janiak, Christoph,Müller, Thomas J. J.
, p. 8114 - 8125 (2018/04/02)
2-Substituted 3-ethynylquinoxaline chromophores can be readily synthesized by a consecutive activation–alkynylation–cyclocondensation (AACC) one-pot sequence in a three-component manner. In comparison with the previously published four-component glyoxylation starting from electron-rich π-nucleophiles, the direct activation of (hetero)aryl glyoxylic acids allows the introduction of substituents that cannot be directly accessed by glyoxylation. By introducing N,N-dimethylaniline as a strong donor in the 2-position, the emission solvatochromicity of 3-ethynylquinoxalines can be considerably enhanced to cover the spectral range from blue–green to deep red–orange with a single chromophore in a relatively narrow polarity window. The diversity-oriented nature of the synthetic multicomponent reaction concept enables comprehensive investigations of structure–property relationships by Hammett correlations and Lippert–Mataga analysis, as well as the elucidation of the electronic structure of the emission solvatochromic π-conjugated donor–acceptor systems by DFT and time-dependent DFT calculations with the PBEh1PBE functional for a better reproduction of the dominant charge-transfer character of the longest wavelength absorption band.