Organic Communications Articles

A new and efficient protocol was developed for synthesis of benzothiazoles as a potential antimicrobial and antioxidant agent using γ-Valerolactone (GVL) as catalyst and solvent under environmentally friendly conditions. The developed synthetic protocol represents a very simple and a novel route for the synthesis of 2-substituted benzothiazole derivatives. In addition, an ultrasound irradiation technique was successfully implemented for performing the reactions in shorter reaction times. The synthesized benzothiazoles were evaluated for antimicrobial and antioxidant activity and was analysed for ADME properties.

Graphene quantum dots (GQDs) immobilized nanosilica was prepared under microwave irradiated green reaction conditions and was used as an efficient heterogeneous acid catalyst. The structure of nano-catalyst was characterized by FT-IR, PL, TEM, XRD, FE-SEM, EDS, TGA, and zeta potential. Xanthene derivatives were synthesized in excellent yields using the freshly prepared catalyst and the catalyst could be easily recovered and recycled for 5 times without significant loss of its catalytic activity. The structures of the resulted products were confirmed by FT-IR, 1H-NMR, 13C-NMR spectroscopic techniques.

Fe3O4 supported graphene quantum dots (GQDs) (Fe3O4@GQDs) was prepared under microwave irradiation. Piperidine was bound to Fe3O4@GQDs via its reaction with 3-piperidinopropyltrimethoxysilane and piperidine-functionalized Lewis basic nano-catalyst (Fe3O4@GQDs-Pip) was prepared. This freshly prepared catalyst was evaluated as a heterogeneous magnetic reusable catalyst for the one-pot synthesis of 2-aminochromenes under MW-assisted solvent-free conditions. Two composite particles, Fe3O4@GQDs and Fe3O4@GQDs-Pip were characterized by FT-IR, XRD, SEM, TGA and VSM analytical methods. The catalyst could be easily recovered by magnetic separation and recycled for 5 times without significant loss of its catalytic activity.

In this work, new N-substituted 2-aminopyrrole derivatives were synthesized. Initially, some crotonitriles were prepared by condensation of malononitrile with arylmethylketones, which was followed by conversion of them to the bromocrotonitriles. Finally, the synthesis of new N-substituted 2-aminopyrrole derivates were successfully achieved by cyclization of the bromocrotonitriles of (R)-1-phenylethylamine applying Gewald method.