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Without using any transition metal catalyst, ligand, base, toxic or hazardous reagent, additives/promoters and organic solvent, green Dakin reactions have been successfully carried out by using H2O2 in a natural feedstock extract. The reaction proceeds in neat ‘Water Extract of Banana’ (WEB) at room temperature under aerobic conditions in very short reaction times and, therefore, it is an evergreen and environmentally sound alternative to the existing protocols for the Dakin reaction. In our system, the reaction was found to afford excellent yield for the desired product with different electron-withdrawing and electron-donating hydroxylated benzaldehydes. [ABSTRACT FROM AUTHOR]

Suzuki–Miyaura cross-coupling reaction catalyzed by Pd(OAc)2–(DHQD)2PHAL is a very simple, mild and efficient protocol for the synthesis of biaryls/heterobiaryls in neat H2O at room temperature. The catalyst system is recyclable/reusable and can be employed in several consecutive runs without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: Tripodal ligands, 1,1,1-tris(diphenylphosphinomethyl)ethane [CH3C(CH2PPh2)3] [P 3 ] and 1,1,1-tris(diphenylphosphinomethyl)ethane trisulphide [CH3C(CH2P(S)Ph2)3] [P 3 S 3 ] have been introduced to stabilize Pdo-nanoparticles having small core diameter and narrow size distribution. The Pdo-nanoparticles were synthesized by the reduction of K2PdCl4 precursor with NaBH4 in the presence of ligand P 3 or P 3 S 3 using two phases, one pot reaction at room temperature. TEM and XRD studies indicate that P 3 stabilizes smaller sized Pdo-nanoparticles (<3nm) compared to that stabilized by P 3 S 3 (<5nm), which are attributable to the stronger interaction of Pdo (Soft) with P (Soft) than Pdo (Soft) with S (less Softer than P). The Pdo-nanoparticles exhibit face centered cubic (fcc) lattice geometry and high thermal stability (∼150°C). The synthesized Pdo-nanoparticles serve as an efficient catalyst for the carbonnd formation reactions, e.g. in Suzuki coupling reaction, aryl halides and arylboronic acids result cross-coupling products with about 94% isolated yield and 100% selectivity; in Heck coupling reaction, the vinylation of aryl halides with olefins result coupling products with 97% yield and >99% trans selectivity while in the alkynylation of aryl halides with terminal alkynes, i.e. Sonogashira coupling reaction, the cross-coupling products of about 94% isolated yield with 100% selectivity were observed. The synthesized nanocatalysts could be reused without significant loss of their catalytic activity. [Copyright &y& Elsevier]