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The Hirao reaction involving the phosphinoylation or phosphonation of aryl halides by >P(O)H reagents is a P-C bond forming transformation belonging to the recently very hot topic of cross-couplings. The Pd- or Ni-catalyzed variations take place via the usual cycle including oxidative addition, ligand exchange, and reductive elimination. However, according to the literature, the nature of the transition metal catalysts is not unambiguous. In this feature article, the catalysts described for the Pd(OAc) 2 -promoted cases are summarized, and it is concluded that the "(HOY 2 P) 2 Pd(0)" species (Y = aryl, alkoxy) is the real catalyst. In our model, the excess of the >P(O)H reagent served as the P-ligand. During the less studied Ni(II)-catalyzed instances the "(HOY 2 P)(-OY 2 P)Ni(II)Cl - " form was found to enter the catalytic cycle. The newest conclusions involving the exact structure of the catalysts, and the mechanism for their formation explored by us were supported by our earlier experimental data and theoretical calculations.

This study aimed to assess the efficacy of a bimetallic system consisting of Mg0 -Pd0 and the bacterium Acinetobacter sp. for the complete detoxification of lindane. Our results demonstrate that palladium immobilized on activated charcoal achieved a removal rate of >99% for 100 mg.L-1 of Lindane within 10 minutes, with the accumulation of trace amounts of intermediates. The reductive transformation of lindane followed 1st-order kinetics, with a calculated rate constant (kobs) of 0.77 min-1. The bimetallic system resulted in the formation of a non-toxic hydrocarbon as the end-product, indicating complete dehalogenation of lindane. Furthermore, Acinetobacter sp. effectively mineralized >98% of 100 mg.L-1 of Lindane after 26 h of cultivation without any accumulation of toxic metabolite(s) in the reaction medium, demonstrating the efficiency of the biological system. Integrating both chemical and biological systems could provide significant advantages for the treatment of lindane, reducing the treatment time and overall cost. This synergistic approach can significantly enhance the overall removal efficiency of lindane from contaminated soil and water. [ABSTRACT FROM AUTHOR]

A recyclable and non‐phosphine solid palladium (II) catalyst was prepared and characterized by HR‐MS, FT‐IR, XPS, EDS, TGA, SEM, TEM and ICP. The Pd‐catalyst exhibited high‐performance catalytic activity in Suzuki and Heck C‐C coupling reactions in an environmentally benign water medium. Further, the Pd‐catalyst (Z4) can be reused for 15 times with little decrease of activity through simple and efficient recovery. In addition, the turn‐over number (TON) of Pd‐ catalyst can reach 380 at room temperature. These results proved that the Pd‐catalyst has a stable structure and can be recycled many times, making the process sustainable. [ABSTRACT FROM AUTHOR]

Abstract: An original synthetic route toward dibenzo[b,e][1,4]diazepin-11-ones and analogues pyridobenzodiazepinones has been developed. The method relies upon an intramolecular amination process between an (hetero)aryl halide and the appropriate aniline moiety. [Copyright &y& Elsevier]

• Palladium(II)-Pivaloyl thiourea complexes successfully synthesized and characterized. • The Pd(II) complexes gave significant results in the Sonogashira catalytic activity. • MC3 with no substitution exhibit the best catalyst as it gave a high conversion rate. We report herein the synthesis of Pd(II) complexes featuring pivaloylthiourea derivatives to investigate their catalytic behaviour in Sonogashira cross-coupling reactions as the homogenous catalyst. The SN 2 reactions have resulted in pivaloyl thiourea derivatives ligands with general formula (CH 3) 3 C(O)NHC(S)NHR introducing different substituent groups of NO 2 (L1), OCH 3 (L2), and H (L3) prior to form complexation with Pd(II) (MC1 , MC2 , and MC3 respectively). All synthesised compounds were characterised via typical selected spectroscopic and analytical methods. Hence, catalytic screening activity revealed that Pd(II)-pivaloyl thiourea catalysed, featuring MC3, is the best catalyst as it gave a high conversion rate up to 99%. [ABSTRACT FROM AUTHOR]