6525-45-7Relevant academic research and scientific papers
Acyl Cyanides as Bifunctional Reagent: Application in Copper-Catalyzed Cyanoamidation and Cyanoesterification Reaction
Chen, Zhengwang,Wen, Xiaowei,Zheng, Weiping,He, Ruolan,Chen, Dou,Cao, Dingsheng,Long, Lipeng,Ye, Min
, p. 5691 - 5701 (2020/04/10)
Cu-catalyzed domino decyanation and cyanation reaction of acyl cyanides with amines or alcohols have been developed. The cyano sources were generated in situ via C-CN cleavage yielding the corresponding cyano substituted amides or esters in moderate to excellent yields. This approach features a cheap copper catalyst, domino decyanation and cyanation reaction, readily available starting materials, broad substrate scope, operational simplicity, and the potential for further transformation of the cyano group.
Skeletal rearrangement of cyano-substituted iminoisobenzofurans into alkyl 2-cyanobenzoates catalyzed by B(C6F5)3
Li, Jing,Okuda, Yasuhiro,Zhao, Jiaji,Mori, Seiji,Nishihara, Yasushi
supporting information, p. 5220 - 5223 (2014/12/11)
An efficient method for the direct conversion of cyano-substituted iminoisobenzofurans into their corresponding alkyl 2-cyanobenzoates has been developed. This transformation proceeds via cleavage of C-C, C-O, and C-N bonds in starting iminoisobenzofurans. DFT study revealed that intermediate α-iminonitriles are produced in situ via C-C bond formation between 2-iminium benzoates and a cyanide ion. Generation of isocyanide as the byproduct in a more thermodynamic manner in DFT calculations also supports the experimental results.
Influence of solvent on the ortho substituent effect in the alkaline hydrolysis of phenyl esters of substituted benzoic acids
Nummert, Vilve,Piirsalu, Mare,Koppel, Ilmar A.
experimental part, p. 497 - 504 (2011/08/08)
The second-order rate constants k (dm3mol-1 s -1) for the alkaline hydrolysis of phenyl esters of meta-, para-and ortho-substituted benzoic acids in aqueous 5.3 M NaClO4 and 1.0 M Bu4NBr were measured by UV/Vis spectrophotometry at 25 °C. The variations in the ortho inductive, ortho resonance, as well as meta and para polar effects with solvent parameters were studied using data for the alkaline hydrolysis of phenyl esters of substituted benzoic acids in various media. The dependence of the ortho substituent effect on solvent can be precisely described with the following equation: δlog kortho = log k ortho - log kH = 0.059 + 2.19σ1 +0.304σ°R + 2.79EBs -0.016 δEσ1-0.085δEσ°R, where δE is the solvent electrophilicity, δE = ES-E H2O, characterizing the hydrogen-bond donating power of the solvent. The increase in the meta and para polar substituent effects with decrease in the solvent hydrogen-bond donor capacity (electrophilicity) was approximately to the same extent (-0.068δEσ°m, p) as the resonance term for the ortho substituents. The steric term of ortho substituents was independent of the solvent parameters. The variations in the ortho inductive, ortho resonance, as well as meta and para polar substituent effects with the solvent electrophilicity were to the same extent as in phenyl benzoates containing the substituents in the phenyl part. The substituent effects in the alkaline hydrolysis of ethyl benzoates appeared to vary with the solvent electrophilicity nearly to the same extent as in the alkaline hydrolysis of substituted phenyl esters of benzoic acids. Copyright 2009 John Wiley Sons, Ltd.
Effect of ortho substituents on carbonyl carbon 13C NMR chemical shifts in substituted phenyl benzoates
Nummert, Vilve,Piirsalu, Mare,Maeemets, Vahur,Vahur, Signe,Koppel, Ilmar A.
experimental part, p. 1155 - 1165 (2010/07/13)
13C NMR spectra of 37 ortho-, meta-, and para-substituted phenyl benzoates, containing substituents in benzoyl and phenyl moiety, 4 ortho-substituted methyl and 5 ethyl benzoates as well as 9 R-substituted alkyl benzoates have been recorded. The influence of the ortho substituents on the carbonyl carbon 13C NMR chemical shift, δCO, was found to be described by a linear multiple regression equation containing the inductive, σI, resonance, σRo, and steric, EsB, or ν substituent constants. For all the ortho-substituted esters containing substituents in the acyl part as well as the phenyl part, the substituent-induced reverse inductive effect (ρIR > 0), and the negative steric effect (δorthosB were observed. In the case of ortho substituents in the phenyl part, the resonance effect was negligible. Due to inductive effect, the ortho electron-withdrawing substituents showed an upfield shift or shielding of the carbonyl carbon, while the electron-donating substituents had an opposite effect. Because of the sterical consequences, ortho substituents revealed a deshielding effect on the 13C NMR chemical shift of the carbonyl carbon. For all the meta- and para-substituted esters, the reverse substituent-induced inductive and resonance effects (ρIR4NBr and 2.25M Bu4NBr, and the IR frequencies, νCO, for the ortho-, meta-, and para-substituted phenyl benzoates and alkyl benzoates were correlated nicely with the corresponding 13C NMR substituent chemical shifts, ΔδCO. Copyright
A bio-inspired copper catalyst system for practical catalytic cyanation of aryl bromides
Schareina, Thomas,Zapf, Alexander,Cotte, Alain,Mueller, Nikolaus,Beller, Matthias
experimental part, p. 3351 - 3355 (2009/06/06)
A general and environmentally improved protocol for the cyanation of aryl halides with the nontoxic cyanide source potassium hexacyanoferrate(II) {K 4[Fe(CN)6]} using copper catalysis and a ligand system based on 1-alkyl-1H-imidazoles is presented. The advantages of this system are a wide substrate range, high selectivity, easy handling, and inexpensive reagents.
A state-of-the-art cyanation of aryl bromides: A novel and versatile copper catalyst system inspired by nature
Schareina, Thomas,Zapf, Alexander,Maegerlein, Wolfgang,Mueller, Nikolaus,Beller, Matthias
, p. 6249 - 6254 (2008/02/13)
A general protocol for the cyanation of aryl halides with the nontoxic cyanide source K4[Fe(CN)6] using copper catalysis and a ligand system based on 1-alkylimidazoles is presented. The advantages of this system are the high selectivity, a unique substrate range, easy handling, and inexpensive reagents.
An efficient catalyst for PD-catalyzed carbonylation of aryl arenesulfonates
Cai, Chaoxian,Rivera, Nelo R.,Balsells, Jaume,Sidler, Rick R.,McWilliams, J. Christopher,Shultz, C. Scott,Sun, Yongkui
, p. 5161 - 5164 (2007/10/03)
(Chemical Equation Presented) Aryl carboxylic esters were synthesized by Pd-catalyzed carbonylation of aryl p-fluorobenzenesulfonates or -tosylates. A unique Josiphos ligand was discovered through high-throughput catalyst screening, which was the key for the successful carbonylation of various substrates. This catalyst is effective and works well for both electron-rich and electron-poor aryl arenesulfonates. Isolated yields of up to 90% were obtained for aryl p-fluorobenzenesulfonates and -tosylates.
