Solvent-Free Buchwald–Hartwig Amination of Heteroaryl Chlorides by <i>N</i>‑Heterocyclic Carbene–Palladium Complex (SIPr)^Ph2Pd(cin)Cl at Room Temperature

Using the robust N-heterocyclic carbene–palladium complex (SIPr)Ph2Pd(cin)Cl, a highly efficient and easy-to-operate method has been developed at room temperature for the solvent-free Buchwald–Hartwig amination of heteroaryl chlorides with various amines. The amount of catalyst can be as low as 0.05 wt %. The system was demonstrated on 47 substrates and successfully applied to the synthesis of commercial pharmaceuticals and candidate drugs with high yields. Furthermore, the protocol can be used to prepare aniline derivatives on a multigram scale without yield loss

Chalcone-Based Synthesis of Tetrahydropyridazines via Cloke–Wilson-Type Rearrangement-Involved Tandem Reaction between Cyclopropyl Ketones and Hydrazines

A facile and efficient approach for the synthesis of multisubstituted tetrahydropyridazines starting from cyclopropyl ketones and hydrazines has been developed. The transformation is chalcone-based and takes place via a Cloke–Wilson-type rearrangement-involved tandem reaction catalyzed by TfOH in HFIP