Malononitrile

The Brookfield DV-II + Pro EXTRA viscometer was used to measure solvent viscosity, and the G LAB melting point apparatus was used to measure the melting point of solvent and derivatives. The ¹H, and ¹³C NMR spectra, CHNS/O elemental analyzer, and mass analysis of compounds were prepared using the Varian Inova 500MHz, the EMA 502, and the Agilent technologies 5975C. The Thermo biomate 5 Spectrophotometer was used to prepare the suspension of bacteria. The suspension of bacteria was obtained from the American Type Culture Collection (ATCC). All the reagent materials used for the synthesis of deep eutectic solvent and the synthesis of pyrazole derivatives and pyrano[2,3-c] pyrazole derivatives such as choline chloride, urea, malononitrile, aldehyde derivatives, and hydrazine derivatives were obtained from Merck and Sigma.

The following reagents were used in the synthesis reaction of o-chlorobenzylidene malononitrile: o-chlorobenzaldehide (C₇H₅ClO, CAS Registry Number 89-98-5, MW 140 g/mol, Thermo Scientific, 97% purity), malononitrile (C₃H₂N₂, CAS Registry Number 109-77-3, MW 66 g/mol, Sigma-Aldrich, 99% purity) and diethylamine (C₄H₁₁N, MW 73 g/mol, CAS Registry Number 109-89-7, Sigma-Aldrich, 99.5% purity) as a catalyst. o-Chlorobenzylidene malononitrile was synthesized in-house via a condensing reaction between o-chlorobenzaldehide and malononitrile (Figure 1), in the presence of diethylamine [33 (link),34 ,35 ,36 ].
The two -CN groups in the malonic nitrile molecule are strongly electron-attracting and activate the CH₂ group to which they are linked, and because of this, malononitrile plays the role of a methylene component in condensation reactions with aldehydes or ketones. The reaction takes place in the presence of catalysts such as secondary or tertiary amines (piperidine, diethylamine, etc.). In the synthesis reaction of CBM, we used diethylamine. The working installation for the synthesis of CBM is presented in Figure 2. The purity of CBM was checked via gas GC-MS in methylene chloride (DCM, Supra Solv, purity of 99.8%) as an organic solvent [37 (link)].

All chemical substances have been used as bought from Sigma-Aldrich and Merck Companies. Tetraethyl orthosilicate (tetraethoxysilane) (98% w/w), ethanol (99.5% w/w), (3-aminopropyl) triethoxysilane (95% w/w), HNO₃ (65% w/w), and silver nitrate (≥ 99.0%), potassium persulphate (99.99%), hydrazine hydrate (24–26% in H₂O (RT)), isatin (97%), acenaphthene quinone (97%), malononitrile (98%), ethyl cyanoacetate (98%), dimedone (95%), barbituric acid ethyl acetoacetate (99%), 4-hydroxycoumarin (98%), three-methyl-1H-pyrazole-five (4H)-one (98%), α-naphthol (99%), β-naphthol (99%), n-hexane (99%), ethyl acetic acid (99%), and desired derivations have been provided from the Sigma-Aldrich Company. The stem and roots of the Spear Thistle were purchased from a local shop in Tehran (in Iran). The leaves were purchased from a local shop in Tehran. The plant we used in this work is a plant that is found in abundance in local shops and is not wild and endangered. This study complies with relevant institutional, national, and international guidelines and legislation.

The nitroketene dithioacetals, cysteamine hydrochloride, isatin, malononitrile, ethyl cyanoacetate, methyl cyanoacetate, cyanoacetohydrazide, barbituric acid, derivatives of isatin, triethylamine and solvents were obtained from Sigma Aldrich and used without further purification. Nano-silica (CAB-O-SIL® M5) was obtained from Cabot Co. IR spectra: Bruker Tensor 27 spectrometer. NMR spectra: Bruker DRX-300 Avance instrument (300 MHz for ¹H and 75.4 MHz for ¹³C) with DMSO-d₆ as solvents. Chemical shifts are expressed in parts per million (ppm), and coupling constant (J) are reported in hertz (Hz). Mass spectra: Agilent 5975C VL MSD with Triple-Axis detector operating at an ionization potential of 70 eV. Elemental analyses for C, H and N: Heraeus CHNO-Rapid analyzer. Melting points: electrothermal 9100 apparatus.