Pesticide carrier systems are highly desirable in achieving the effective utilization of pesticides and reduction of their loss. In order to increase utilization and enhance pesticide adhesion to harmful targets, adhesive and stimulus-responsive nanocomposites were prepared using graphene oxide (GO) and polydopamine (PDA). The results demonstrated that graphene oxide with a layer of PDA had a high hymexazol-loading capacity. The release curve of hymexazol from the nanocomposite showed that the release was NIR-laser-dependent and pH-dependent. The adhesion-performance investigation demonstrated that Hy-GO@PDA exhibited greater hymexazol persistence than a hymexazol solution after a simulated-rainwash experiment, and it also left more hymexazol residue than a hymexazol solution with a surfactant under high concentrations. Finally, the bioactivity of the prepared hymexazol-loaded nanocomposite was measured against Fusarium oxysporum f. sp. cucumebrium Owen, and it showed an inhibition activity similar to that of the hymexazol solution. All of these revealed that GO with a PDA layer could serve as pesticide carrier to solve low-utilization and wash-off problems, especially for water-soluble pesticides.

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An efficient palladium-catalyzed cross-coupling reaction of azides with isocyanides is developed, providing a general synthetic route to unsymmetric carbodiimides with excellent yields. This method shows a broad substrate scope, including not only aryl azides, but also unactivated benzyl and alkyl azides. Furthermore, from readily available substrates, Pd-catalyzed coupling with a tandem amine insertion cascade to obtain unsymmetric trisubstituted guanidines has been achieved in a one-pot fashion.

A Rh(III)-catalyzed C-H activation of boronic acid with aryl azide to obtain unsymmetric carbazoles, 1 H-indoles, or indolines has been developed. The reaction constructs dual distinct C-N bonds via sp/sp C-H activation and rhodium nitrene insertion. Synthetically, this approach represents an access to widely used carbazole derivatives. The practical application to CBP and unsymmetric TCTA derivatives has also been performed. Mechanistic experiments and DFT calculations demonstrate that a five-membered rhodacycle species is the key intermediate.