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Benzoylhydrazone Schiff base–ligated three new ONO pincer–type palladium(II) complexes, [(PdL1(PPh3)] (1), [(PdL2(PPh3)] (2), and [(PdL3(PPh3)] (3), were synthesized by the reaction of the respective ligand, N‐(2‐hydroxybenzylidene)benzohydrazide (HL1), N‐(2‐hydroxy‐3‐methoxybenzylidene)benzohydrazide (HL2), or N‐(5‐bromo‐2‐hydroxybenzylidene) benzohydrazide (HL3), with Pd(OAc)2 and PPh3 in methanol and isolated as air‐stable reddish‐orange crystalline solids in high yields (78%–83%). All three complexes were fully characterized by elemental analysis, Fourier‐transform infrared spectroscopy, UV–Visible, 1H nuclear magnetic resonance (NMR), 13C{1H} NMR, and 31P{1H} NMR spectroscopic studies. The molecular structure of all three complexes was established unambiguously by single‐crystal X‐ray diffraction studies which revealed a distorted square planar geometry of all three complexes. The ONO pincer–type ligands occupied three coordination sites at the palladium, while the fourth site is occupied by the monodentate triphenylphosphine ligand. The catalytic potential of all three complexes was explored in the carbonylative Suzuki coupling of aryl bromides and iodides with arylboronic acids to yield biaryl ketones, using CHCl3 as the source of carbonyl. The reported protocol is convenient and safe as it obviates the use of carbon monoxide (CO) balloons or pressured CO reactors which are otherwise needed for the carbonylation reactions. The methodology has been successfully applied to the synthesis of two antineoplastic drugs, namely, phenstatin and naphthylphenstatin, in good yields (81% and 85%, respectively). Under the optimized reaction conditions, complex 2 exhibited the best catalytic activity in the carbonylative Suzuki couplings. The reported catalysts have wide reaction scope with good functional group tolerance. All catalysts could be retrieved from the reaction after completion and recycled up to three times with insignificant loss in the catalytic activity. [ABSTRACT FROM AUTHOR]

An environment benign process has been developed for the regioselective synthesis of 5-iodo-1,4-disubstituted-1,2,3-triazoles catalyzed by CuI/β-CD in water. Moreover, the process was manifested for the efficient synthesis of 2-iodo-imidazo[1,2- a ]pyridines and 2-iodo-benzoimidazo[2,1- b ]thiazoles in aqueous medium. Additionally, the iodinated derivatives were successfully modified via palladium catalyzed coupling reactions. The salient features of this methodology are in-situ formation of 1-iodoalkyne & alkyl/aryl azide under mild reaction conditions, high regio-selectivity and use of water as a greener solvent. [ABSTRACT FROM AUTHOR]

The reaction has a good functional group tolerance. [ABSTRACT FROM AUTHOR]

The title reaction is catalyzed by Pd(OAc)2 and uses Cu(OTf)2 as an oxidative cocatalyst and molecular oxygen as the terminal oxidant. [ABSTRACT FROM AUTHOR]

The reaction cascade combines a Chan-Lam type coupling and a subsequent Ullmann type coupling. [ABSTRACT FROM AUTHOR]

The selective N-arylation of heterocycles with a series of arylboronic acids under base free conditions at ambient atmosphere is presented. [ABSTRACT FROM AUTHOR]

Suzuki-Miyaura cross-coupling of (het)arylboronic acids with chromene derivative (I) provides the corresponding 5-(het)arylated chromenes that can be subjected to Cadogan reaction to give the title compounds. [ABSTRACT FROM AUTHOR]

Under ligand- and base-free conditions imidazole-containing heterocycles are formed in the presence of copper(I) salts. [ABSTRACT FROM AUTHOR]

Three component condensation of 1,3-diaryl-2-propen-1-ones with ethyl nitroacetate and ammonium acetate provides a convenient synthesis of 4,6-diarylated pyridin-2(1H)-ones. [ABSTRACT FROM AUTHOR]

Transamidation of a series of N,N-dimethyl amides with a wide range of primary and secondary amines is accomplished environmentally friendly using sulfuric acid adsorbed on silica gel as recyclable catalytic system. [ABSTRACT FROM AUTHOR]

5- And 6-aminoindazoles are arylated using various arylboronic acids and the products are cyclized to pyrazolocarbazoles. [ABSTRACT FROM AUTHOR]

A three step path is developed to prepare the target compounds, including a cyclization to construct the chromene fragment [cf. [ABSTRACT FROM AUTHOR]