671210-48-3Relevant academic research and scientific papers
Highly Selective and Sensitive Colorimetric and Fluorescent Chemosensors for Rapid Detection of Cyanide Anions in Aqueous Medium: Investigation on Supramolecular Recognition of Tweezer?shaped Salophenes
Darabi, Hossein Reza,Nazarian, Ramo,Alizadeh, Sepideh,Aghapoor, Kioumars,Ebadinia, Leila
, p. 1085 - 1097 (2021)
Three tweezer?shaped salophenes having catechols (1), phenols (2) and anisoles (3) units in conjunction to the dipodal Schiff bases have been applied for the optical sensing of cyanide (CNˉ) ions in CH3CN-H2O (7:3) as solvent of choi
Synergistic effect of copper nanocrystals-nanoparticles incorporated in a porous organic polymer for the Ullmann C-O coupling r–eaction
Gorginpour, Forough,Zali-Boeini, Hassan
, (2021/02/22)
A quinoxaline-based porous organic polymer (Q-POP) as a mesoporous organic copolymer was developed as a new platform for the immobilization of CuNPs and copper nanocrystals. The prepared materials were characterized by FT-IR, XRD, N2 adsorption-desorption isotherms, ICP, TGA, SEM, HR-TEM, EDX, and single-crystal X-ray crystallography. The obtained catalyst presented extraordinary catalytic activity towards Ullmann C–O coupling reactions with high surface area, hierarchical porosity, and excellent thermal and chemical stability. Due to its high porosity, and synergistic effect of copper nanocrystals incorporated in the polymer composite, the as-synthesized catalyst was successfully utilized for the Ullmann C–O coupling reaction of phenols and different aryl halides to prepare various diaryl ether derivatives. All types of aryl halides (except aryl fluorides) were screened in the Ullmann C–O coupling reaction with phenols to produce diaryl ethers in good to excellent yields (70–97 %), and it was found that aryl iodides have the best results. Besides, due to the strong interactions between CuNPs, N, and O-atoms of quinoxaline moiety existing in the polymeric framework, the copper leaching from the support was not observed. Furthermore, the catalyst was recycled and reused for five consecutive runs without significant activity loss.
A quinoxaline-based porous organic polymer containing copper nanoparticles CuNPs@Q-POP as a robust nanocatalyst toward C-N coupling reaction
Gorginpour, Forough,Zali-Boeini, Hassan,Rudbari, Hadi Amiri
, p. 3655 - 3665 (2021/02/03)
A novel porous organic polymer (denoted by Q-POP) was successfully fabricated by free-radical copolymerization of allyl-substituted 2,3-di(2-hydroxyphenyl)1,2-dihydroquinoxaline, and divinylbenzene under solvothermal conditions and used as a new platform for immobilization of copper nanoparticles. The CuNPs@Q-POP nanocatalyst was prepared via incorporating of Cu(NO3)2 into the polymeric network, followed by the reduction of Cu2+ ion with hydrazine hydrate. The obtained materials were characterized through FT-IR, XRD, N2 adsorption-desorption isotherms, ICP, TGA, SEM, HR-TEM, EDX, and the single-crystal X-ray crystallography. The results displayed that Q-POP and CuNPs@Q-POP possessed high surface area, hierarchical porosity, and excellent thermal and chemical stability. The as-synthesized catalyst was utilized for the Ullmann C-N coupling reaction of aromatic amines and different aryl halides to prepare various diarylamine derivatives. All types of aryl halides (except aryl fluorides) were screened in the Ullmann C-N coupling reaction with aromatic amines to produce diaryl amines in good to excellent yields (50-98%), and it turned out that aryl iodides have the best results. Besides, due to the strong interactions between CuNPs, N, and O-atoms of quinoxaline moiety existing in the polymeric framework, the copper leaching from the support was not observed. Furthermore, the catalyst was recycled and reused for five consecutive runs without significant activity loss.
Ene-diamine versus imine-amine isomeric preferences
Reich, B. Jesse E.,Greenwald, Erin E.,Justice, Aaron K.,Beckstead, Brittany T.,Reibenspies, Joseph H.,North, Simon W.,Miller, Stephen A.
, p. 8409 - 8416 (2007/10/03)
Cyanide-catalyzed aldimine coupling was employed to synthesize compounds with 1,2-ene-diamine and α-imine-amine structural motifs: 1,2,N,N′-tetraphenyletheylene-1,2-diamine (13) and (±)-2,3-di-(2- hydroxyphenyl)-1,2-dihydroquinoxaline (17), respectively. Single-crystal X-ray diffraction provided solid-state structures and density functional theory calculations were used to probe isomeric preferences within this and the related hydroxy-ketone/ene-diol system. The ene-diamine and imine-amine core structures were calculated (B3LYP/6-311++G(d,p)) to be essentially identical in energy (ΔG = 0.2 kcal/mol in favor of the imine-amine, within the error of the calculation). However, additional effects-such as π conjugation-in 13 render an ene-diamine structure that is slightly more stable than the imine-amine tautomer (14) (ΔG = 0.2-0.7 kcal/mol, within the error of the calculation). In contrast, the intramolecular hydrogen bonding present in 17 significantly favors the imine-amine isomer over the ene-diamine tautomer (18) (ΔG = 7.2-8.9 kcal/mol). For both 13 and 17, the optimized calculated structures (B3LYP/6-31+G(d′)) are identical to those observed by single-crystal X-ray diffraction.
Cyanide-Catalyzed Cyclizations via Aldimine Coupling
Reich, B. Jesse E.,Justice, Aaron K.,Beckstead, Brittany T.,Reibenspies, Joseph H.,Miller, Stephen A.
, p. 1357 - 1359 (2007/10/03)
Aldimine coupling (AIC) is the nitrogen analogue of the benzoin condensation and has been applied to dialdimines, providing the first examples of cyclizations effected by cyanide-catalyzed AIC. Sodium cyanide promoted the facile, intramolecular cyclization of several dialdimines in N,N-dimethylformamide, methanol, or methylene chloride/water (phase-transfer conditions) yielding a variety of six-membered heterocycles. Under aerobic conditions, an oxidative cyclization occurs to provide the diimine heterocycle. Oligomerization was observed with rigid dialdimines for which cyclization was precluded.
