Most of the metal-catalyzed C–H activation/annulation reactions were carried out in organic solvents using expensive oxidants such as Cu(II) and Ag(I) salts. Here, we reported a new approach for a highly regioselective synthesis of isoquinolones from N-alkyl benzamides and alkynes using an Rh(III) catalyst and inexpensive oxygen as the sole oxidant in an aqueous medium. In the reaction, water gave the highest product yield among the solvents used. In addition, at the end of the reaction, the isoquinolone product directly precipitated out from the aqueous solution. The methodology can be applied to a gram scale synthesis. This Rh(III)-catalyzed reaction shows interesting meta selectivity with the meta substituted benzamide and shows various regioselectivities with different substituted alkynes. Moreover, the methodology can be applied to the preparation of biologically active compounds having the isoquinolone core.

Palladium-catalyzed oxidative carbonylation of 2-arylphenols through C–H bond activation and C–C and C–O bond formation under acid–base free and mild conditions has been developed. The reaction tolerates a variety of substrates and provides biologically important benzopyranone derivatives in up to 87% isolated yield.

We demonstrated that two Lewis bases – urea and thiourea – acted as efficient additives for CH₃NH₃(MA)PbI_3−xCl_x and MAPbI₃ perovskite solar cells (PSCs) and observed a significant increase in PCE for the MAPbI₃ devices in the presence of 1% urea with a remarkable PCE of 18.8% using an extremely low annealing temperature (85 °C).