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The synthesis of various benzofurans via Sonogashira coupling catalyzed by palladous acetate-derived Pd(0) nanoparticles is reported.

K2CO3-mediated reaction of 2,4- and 2,6-difluoronitrobenzenes at 120 °C provides the corresponding dialkylaminonitrobenzenes (III) and (VI), respectively.

The applied catalytic system can be recycled at least four times and reused without significant loss of activity.

Eu3+-doped Ba3Ca3(PO4)4 red-emitting phosphors are synthesized by solid state reaction of BaCO3, CaCO3, NH4H2PO4, and Eu2O3 (porcelain crucible, 1000 °C, 6 h).

Oxo-molybdenum chemistry is of great interest since such units are found in the active sites of a majority of molybdo-enzymes. In order to mimic the biological systems, a number of oxo-molybdenum complexes have been synthesised and studied. This review describes synthesis, structure and applications of oxo-molybdenum complexes particularly cis-MoO2(L)(D) where L stands for a dianionic tridentate ONO ligand and D for a donor solvent molecule/monodentate ligand. The ligand moieties are derived from Schiff base, hydrazide Schiff base and other related tridentate ligands L(H)2. The coordination geometry around the Mo center in these complexes can be best described as a distorted octahedron in which the ONO-tridentate ligand occupies meridional position with two anionic oxygen donors mutually trans and are cis to the oxygen centers of the cis-dioxo group. Mostly the applications of cis-MoO2-(ONO) type complexes seen in literature are oxo transfer reactions like epoxidation, sulfoxidation and phosphine oxidation reactions.

Synthesis of [2]catenane 6 has been successfully achieved by the combination of Pd complex 1 and pyridines 2 and 3 at a molar ratio of 2:1:1 in D20. A mixture of square molecule 4 (prepared from 1 and 2) and macrocycle 5 (obtained from 1 and 3), in which the final ratio of 1, 2, and 3 was kept 2:1:1 reorganizes in D2O/CD3OD (1:1) to form 6 within one day. However, the same mixture in D2O shows the formation of novel [3]catenane 7 along with the [2]catenane. In order to make 7, the theoretical ratio of components 1, 2, and 3 should be 3:1:2. Thus, deliberately maintaining such ratio of the above-mentioned molecules, a higher proportion of the [3]catenane is observed in D2O as found from 1H NMR spectra of the system. Reorganization of the twelve components to form [3]catenane is supported by studies with the DOSY method. This method is a first attempt to separate, from a mixture, either catenanes or any other supramolecular self-assembly structures. CSI-MS studies further support the assigned catenane super structures 6 and 7. All the results indicate that the [2]catenane is thermodynamically the most stable structure, while the [3]catenane is a meta-stable self-assembly.

The role of MoO2Cl2 and some complexes containing MoO2Cl2 as catalysts for various Lewis acid catalysed organic transformations, oxidation and reduction reactions is reviewed.

Synthesis of β-keto esters by condensing various aldehydes with ethyl diazoacetate is achieved by using molybde-num(VI) dichloride dioxide. Aromatic, aliphatic, and heterocyclic aldehydes are successfully condensed with ethyl diazoacetate to obtain corresponding β-keto esters in high yields at room temperature.

Transformation of epoxides to β-alkoxy alcohols, acetonides, and α-alkoxy ketones is achieved by using molybdenum(VI) dichloride dioxide (MoO 2 Cl 2 ) as a catalyst. Alcohol, aldehyde, oxime, tosyl, and TERT-butyldimethylsilyl functional groups are tolerated during the methanolysis and acetonidation of the functionalized epoxides. No polymerization product is observed with any of the epoxides. Direct conversion of epoxides devoid of sensitive functional groups into the corresponding α-methoxy ketone is achieved in a single step by using the MoO 2 Cl 2 /Oxone system.