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Herein reported is a nickel-catalyzed reductive aryl thiocarbonylation of alkene via thioester group transfer strategy by using simple and readily available thioesters. In contrast to traditional activation of weaker C­(acyl)–S bond, the C­(acyl)–C bond of thioester was selectively cleaved to enable this reaction under mild conditions. Furthermore, this approach features operational simplicity and broad substrate scope, providing a complementary and practical route for thioester synthesis without requiring toxic thiol or CO gas.

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Herein a palladium/norbornene‐catalyzed sequential ortho‐acylation and ispo‐alkenylation for access to polysubstituted aryl ketones has been developed. By exploiting dicyclohexylcarbodiimide (DCC) as activator, aryl with electron‐donating or electron‐withdrawing functionalities, alkyl, and heteroaryl carboxylic acids were compatible in this transformation, affording the desired products in decent to good yields.

Herein, a three component Catellani-type reaction catalyzed by the Palladium/Norbornene/ CuI (Pd/NBE/CuI) cooperative system by using Nacylph-thalimides as acyl electrophiles is reported, which gives access to a series of aromatic ketones. The transformation is performable in the presence of water, albeit with decreased reaction yield. The additive CuI was crucial to facilitate the cleavage of C(O)À N bond of imide. This protocol showed broad substrate scope: both alkyl and aryl acyl groups could be installed at the ortho-position of aryl iodides; alkenes and boronic acids can be used as termination reagents.

In this study, the polyethyleneimine (PEI) was grafted onto the biochars from chestnut shells and nori via the cross-linking reaction. Scanning electron microscopy, transmission electron microscopy and Fourier transferred infrared spectroscopy analysis indicated that the PEI was successfully grafted on the surface of biochars. The PEI modified and pristine biochars were used as adsorbents to remove Cr(VI) from aqueous solutions as a function of pH, ionic strength, contact time and initial concentrations of Cr(VI) through batch technique. The strongly pH-dependent and ionic strength-independent of Cr(VI) sorption indicated that the sorption was mainly dominated by electrostatic interaction and inner-sphere surface complexation. The maximum sorption capacities of PEI modified chestnut shell and nori biochars were 141.42 and 222.84 mg/g, respectively, which were significantly higher than those of pristine biochars. The PEI grafted onto the biochars significantly enhanced Cr(VI) sorption capacity because PEI, which contains volumes of amine/imine groups, provided an excellent platform for Cr(VI) ions removal. In addition, the sorption-desorption experimental results indicated that the PEI modified biochars possessed a stable and recyclable performance. All these results manifested that the PEI modified biochars could be applied as environmentally friendly and efficient adsorbents for the removal of Cr(VI) from wastewater.