A number of chalcones were prepared by condensing either 1-acetylnaphthalene or substituted 1-acetylnaphthalenes with 1-naphthaldehyde or 4-dimethylamino-1-naphthaldehyde in ethanolic NaOH solutions. These chalcones were immediately reacted with hydrazine hydrochloride, phenyl hydrazine and semicarbazide hydrochloride in the presence of dry acetic acid to obtain the corresponding 2-pyrazolines. The synthesised heterocycles were characterized on the basis of their chemical properties and spectroscopic data. These compounds were tested for antimicrobial activity against a variety of test organisms: Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabillis, Shigella dysentry and Salmonella typhii. The compounds containing chloro, hydroxo and dimethylamino -N(CH3)2 group as substituents on the naphthalene rings have been found to be very effective antimicrobial agents. In addition, the presence of a carboxamido -CONH2 substituent group at the N-1 position of the 2-pyrazoline rings is shown to contribute substantially to the antimicrobial activity.

The synthesis of fiveand six-membered oxygen-and nitrogen-containing heterocycles has been regarded as the most fundamental issue in organic chemistry and chemical industry because they are used in producing high-value products. In this study, an efficient, economic, sustainable, and green protocol for multicomponent synthesis has been developed. The one-pot direct Knoevenagel condensation−Michael addition−cyclization sequences for the transformation of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin or phthalhydrazide generate the corresponding dihydropyrano[2,3-c]chromenes and 1Hpyrazolo[1,2-b]phthalazine-5,10-diones over a novel mesoporous metal− organic framework-based supported Cu(II) nanocatalyst

Condensation of 2-acetylnaphthalene with benzaldehydes under microwave irradiation affords chalcones which undergo facile and clean cyclizations with hydrazines RNHNH2 (R= H, Ph, Ac) to afford 3,5-arylated 2-pyrazolines in quantitative yields, also under microwave irradiation and in the presence of dry AcOH as cyclizing agent. The results obtained indicate that, unlike classical heating, microwave irradiation results in higher yields, shorter reaction times (2-12 min.) and cleaner reactions.

A porous multifunctional zirconium‐based metal–organic framework (MOF) was achieved by combined covalent and dative post synthetic modification (PSM) of the UiO‐66‐NH2, and characterized by a variety of techniques, including FTIR spectroscopy, powder XRD, N2 temperature‐programmed adsorption/desorption, scanning electron microscopy, thermal gravimetric analysis, inductively coupled plasma atomic emission spectroscopy, and UV/Vis diffuse reflectance spectroscopy. The MOF (Zr–MOF–FePC, PC=2‐pyridinecarboxaldehyde) is an active, efficient, and reusable catalyst for the one‐pot tandem photooxidative Passerini three‐component reaction of alcohols. This is a new type of tandem photocatalyst and cooperative catalyst and was obtained in the course of developing MOFs as versatile heterogeneous catalysts for diverse tandem oxidative multicomponent reactions. This work illustrates the potential of MOFs as multifunctional heterogeneous catalysts for sustainable chemistry.

The multicomponent domino reaction synthesis of dihydro-2-oxopyrroles has been performed using the sulfonated metal–organic framework, UiO-66-SO3H (UiO is the University of Oslo), as a highly efficient acid catalyst.

MIL-125(Ti)-NH has been modified by reaction of salicylaldehyde with the terephthalate amino groups to form a salicylideneimine that act as ligand of Cu. The success of the postsynthetic modification was assessed by FTIR spectroscopy of the MIL-125(Ti)-NH-Sal-Cu and by analysis by H NMR spectroscopy of the organic linkers upon dissolution of MIL-125(Ti)-NH-Sal-Cu. In comparison with parent MIL-125(Ti)-NH and MIL-125(Ti)-NH-Sal, that exhibit a poor activity, the presence of the Cu-Schiff base complex in MIL-125(Ti)-NH-Sal-Cu catalyst for the oxidation of 1-phenylethanol by tert-butylhydroperoxyde (TBHP, 3 eq.) increases notably the catalytic activity. Hot filtration test and reusability experiments confirm that the process is heterogeneous and that MIL-125(Ti)-NH-Sal-Cu is stable under the reaction conditions. Quenching studies and EPR spectra using N-butylphenylnitrone indicate the generation of BuOO andBuO under the reaction conditions. The scope of MIL-125(Ti)-NH-Sal-Cu as oxidation catalyst by BuOOH was studied for benzyl alcohol as well as alicyclic and aliphatic alcohols and ethylbenzene.

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