Synthesis of benzylidenemalononitrile by Knoevenagel condensation through monodisperse carbon nanotube-based NiCu nanohybrids

Abstract

Monodisperse nickel/copper nanohybrids (nicu@MWcnt) based on multi-walled carbon nanotubes (MWcnt) were prepared for the Knoevenagel condensation of aryl and aliphatic aldehydes. the synthesis of these nanohybrids was carried out by the ultrasonic hydroxide assisted reduction method. nicu@MWcnt nanohybrids were characterized by analytical techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (teM), high-resolution transmission electron microscopy (HR-teM), and Raman spectroscopy. According to characterization results, nicu@MWcnt showed that these nanohybrids form highly uniform, crystalline, monodisperse, colloidally stable nicu@MWcnt nanohybrids were successfully synthesized. thereafter, a model reaction was carried out to obtain benzylidenemalononitrile derivatives using nicu@MWcnt as a catalyst, and showed high catalytic performance under mild conditions over 10-180 min. Benzylidenemalononitrile (BMN) derivatives are frequently used as both a target molecule and an intermediate molecule in organic chemistry. BMN derivatives have attracted many scientists' attention because of some unique properties such as anticancer 1-3 , antifungal 4,5 , antibacterial 6-9 , anti-corrosive 10. BMN derivatives are used to increase cell resistance in the case of oxidative stress 11 , in prostaglandin biosynthesis 12 , in the design of photoconductive cells 13 and the inhibition/activation of certain enzymes 14,15. Typically, BMN derivatives are synthesized by the Knoevenagel condensation of aldehydes with active methylene compounds (Fig. 1) 16-22. In these processes, it is seen that it has an effect on homogeneous catalysts. Heterogeneous catalysts have various advantages such as minimum availability, recovery, reusability, structural deterioration resistance and leaching of metal values 23-28. Bimetallic heterogeneous catalysts, in particular, have greatly facilitated the Knoevenagel condensation reaction 29-34. In literature, many catalysts such as SBA-15 (highly stable mesoporous silica) 35 , Sr 3 Al 2 O 6 nanoparticles 36 , bifunctional MIL-101(Cr) 37 , Fe 3 O 4 @SiO 2 nanoparticles 38 and Mn-MOF@Pi 39 have been used in condensation reactions. Herein we report an eco-friendly and practical method for the synthesis of highly efficient, cost-effective, and monodisperse bimetallic NiCu@MWCNT nanohybrids for the Knoevenagel condensation reaction under mild conditions. BMN derivatives have been successfully obtained in a very short time (10-180 min) using the developed method in the water-containing solvent system. experimental chemicals. NiCl 2 , CuCl 2 , NaBH 4 , aminoborane aryl azides, acetonitrile (ACN), lithium perchlorate (LiClO 4), 3,4-ethylene dioxythiophene (EDOT), multiwall carbon nanotubes, NN-Dimethylformamide (DMF), sulfuric acid, hydrochloric acid, and nitric acid were purchased from Sigma-Aldrich. Tetrahydrofuran (THF; 99.5%), HClO 4 (60%), 2-propanol, and Methanol (≥ 99.5%) were obtained from Merck. All test materials and other

Is a Catalyst Always Needed? The Case of the Knoevenagel Reaction with Malononitrile

“…Another example of bimetallic catalyst was monodisperse nickel/copper nanohybrids (NiCu@MWCNT) based on multi-walled carbon nanotubes (MWCNT) that was used at rt in water/methanol (1/1) in short reaction times (entry 20). [51] Recycling procedure was also performed with 4-nitrobenzaldehyde. Under these conditions, this reaction gave complete conversion when carried out in the absence of a catalyst.…”

“…However, under the adopted condition, after 8 min at rt in water/methanol we obtained a precipitate which was filtered and collected indicating that this substrate gave complete conversion without catalyst. Another example of bimetallic catalyst was monodisperse nickel/copper nanohybrids (NiCu@MWCNT) based on multi‐walled carbon nanotubes (MWCNT) that was used at rt in water/methanol (1/1) in short reaction times (entry 20) [51] . Recycling procedure was also performed with 4‐nitrobenzaldehyde.…”

Cerium immobilized carbon nitride: A proficient and recyclable catalyst to construct carbon–carbon double bonds in water

“…[11] One such approach is the condensation between a carbonyl compound and an active methylene moiety-possessing molecule with the utilization of a wide variety of catalysts including mesoporous materials, metal-organic frameworks, bimetallic, mixed oxide, graphitic carbon nitride, and deep eutectic solvents. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] Further, hazardous solvents including tetrahydrofuran, [32,33] dimethyl formamide, [34] alcohols, [35,36] dioxane, [37] toluene, [38] acetonitrile, [39] and dichloromethane [40] have often been used to effect this carbon-carbon bond construction. [41][42][43][44][45][46][47] For instance, Hassan et al [41] showed the capacity of amino-grafted graphene oxide-Fe 3 O 4 in tetrahydrofuran at 50 C, Markad et al [44] exposed the performance of amidefunctionalized 2D coordination polymer (involving a bis-pyridylmethyldiaminobutane diacetamide) in methanol, Taher et al [45] revealed the amine-functionalized metal-organic framework in DMF, Zhong et al [46] discovered the utility of bifunctional mesoporous carbon nitride in toluene at 80 C under ...…”

Symmetric Iodonium Salts Based on Benzylidene as One-Component Photoinitiators for Applications in 3D Printing

“…In a recent study, we proposed new chromospheres based on the benzylidene scaffold . This type of compound has a simple structure that is easy to modify also due to the simplicity of the synthesis . This leads to the possibility of fine-tuning the spectral properties of the chromophore and then the iodonium salt.…”

“…44 This type of compound has a simple structure that is easy to modify also due to the simplicity of the synthesis. 45 This leads to the possibility of fine-tuning the spectral properties of the chromophore and then the iodonium salt. Most of the benzylidene-based iodonium salts presented there were characterized by an absorption band located at about 360 nm.…”