Effect of 2-[3-(trifluoromethyl)phenyl]-4H-furo[3,2-b]pyrrole-5-carboxhydrazides on photosynthetic processes

A new series of carboxhydrazides 6-8 was synthesized under microwave irradiation by reaction of carboxhydrazide 1 with heterocyclic aldehydes 2-4 in the presence of p-toluenesulfonic acid in ethanol. N-Benzoylcarboxhydrazide 9 was prepared by reaction of 1 with benzoylchlorid 5 in THF at room temperature. The effects of 6-9 on inhibition of photosynthetic electron transport in spinach chloroplasts and chlorophyll content in the antialgal suspensions of Chlorella vulgaris were investigated.

Easily recoverable and reusable p-toluenesulfonic acid for faster hydrolysis of waste polyethylene terephthalate

Common technologies for waste polyethylene terephthalate (PET) hydrolysis generally use strong acids or alkalis as catalysts; however, these processes are costly and generate a large amount of acid, alkali, and...

Sintesis gliserol ester berbasis asam oleat sawit dan karakteristik sifat fisika kimia

Peningkatan kapasitas produksi biodiesel menyebabkan meningkatnya produksi gliserol. Salah satu cara alternatif untuk meningkatkan nilai ekonomi gliserol adalah melalui esterifikasi gliserol menjadi surfaktan, yaitu gliserol ester (GE). Penelitian ini bertujuan melakukan sintesis GE berbasis asam oleat sawit dengan waktu reaksi 180 menit menggunakan katalis p-toluenesulfonic acid (PTSA). Suhu sintesis yang digunakan, yaitu:140, 160, 180, dan 240°C. Hasil uji ANOVA dan Duncan (α = 0,05) menunjukkan bahwa suhu sintesis berpengaruh nyata pada rendemen, angka asam, dan viskositas. Proses sintesis GE optimum diperoleh pada suhu sintesis 160°C dengan nilai rendemen GE sebesar 95,66%, pH 7, nilai angka asam 11,28 mg KOH/g sampel, viskositas kinematis 75,76 cst, dan densitas 0,944 g cm-3. Suhu sintesis 160°C, 180°C, dan 240°C menghasilkan rendemen yang tinggi, berkisar 95,66-97,07% dan tidak berbeda nyata antara ketiganya. Analisis menggunakan metode Analytical Hierarchy Process(AHP) juga menghasilkan suhu terbaik untuk sintesis GE adalah 160°C. Produk GE yang terbentuk mengandung gugus ester, asam karboksilat, dan alkohol yang muncul pada 1240,41-1739,62 cm-1.[Kata kunci: biodiesel, esterifikasi, katalis PTSA, surfaktan]

Characterization of a polyaniline/pre-oxidized fiber felt electromagnetic wave absorbing composite

Firstly, a polyaniline/pre-oxidized fiber felt composite was prepared by in situ polymerization using pre-oxidized fiber felt as the substrate, aniline as the monomer, ammonium persulfate as the oxidant, and p-toluenesulfonic acid as the dopant. Secondly, the electromagnetic wave absorbing property and tensile property of the polyaniline/pre-oxidized fiber felt composite were investigated. Finally, the structure and composition were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and differential scanning calorimetry. The results show that the reflection loss of the polyaniline/pre-oxidized fiber felt composite is the smallest at the 3000 MHz frequency, reaching –8.23 dB, and the average surface resistance is 2059.84 Ω, with good conductivity. The characterization analysis shows that polyaniline has been successfully loaded on the pre-oxidized fiber felt, and the protonation reaction occurs at the nitrogen atom on the imine -N-. The polyaniline structure is doped by p-toluenesulfonic acid with a certain degree of order and crystallinity, and the composite has good thermal stability.

In silico investigation of ligand-regulated palladium-catalysed formic acid dehydrative decomposition under acidic conditions

In silico investigation of ligand-regulated palladium-catalysed formic acid dehydrative decomposition to carbon monoxide under acidic conditions was conducted. The contribution from the pyridyl group implanted in pytbpx ligand on enhancing the activity of palladium catalyst and the specific role of para-toluenesulfonic acid as the promoter of dehydration were uncovered.

In silico investigation of ligand-regulated palladium-catalysed formic acid dehydrative decomposition under acidic conditions

In silico investigation of ligand-regulated palladium-catalysed formic acid dehydrative decomposition to carbon monoxide under acidic conditions was conducted. The contribution from the pyridyl group implanted in pytbpx ligand on enhancing the activity of palladium catalyst and the specific role of para-toluenesulfonic acid as the promoter of dehydration were uncovered.

Reactions of 4-hydroxycoumarin with heterocyclic aldehydes

Reactions of 4-hydroxycoumarin 1 with heterocyclic aldehydes 2-4 led to bis-4-hydroxycoumarin derivatives 5-7 under microwave irradiation as well as under the classical heating. The subsequent reactions of products 5-7 are described. 4,4’-Epoxydicoumarins 8, 9 were prepared by the reaction of 5-7 in acetic acid / p-toluenesulfonic acid medium. Compound 10 was prepared by the reaction of 5 in acetic anhydride in the presence sodium acetate. Dioxocine-1,15-dione 11 was prepared by the reaction of 6 with dichloromethane in sodium hydroxide-toluene.