Tertiary amine-directed and involved carbonylative cyclizations through Pd/Cu-cocatalyzed multiple C-X (X = H or N) bond cleavage.

A novel Pd/Cu-cocatalyzed carbonylative cyclization by C-H activation and -dealkylative C-N bond activation has been developed for the chemoselective construction of synthetically useful heterocycles. The ,-dimethylamine group on -indolyl-,-dimethylarylamines was found to act as both the directing group and reactive component in this C-H carbonylative cyclization reaction. Furthermore, a unique C-H oxidation/carbonylative lactonization of diarylmethylamines is firstly demonstrated under modified reaction conditions, which could be easily applicable to the one-step synthesis of multi-substituted phthalides bearing an ,-ketal skeleton that is difficult to access by previously reported methods.

Controllable Si-C Bond Activation Enables Stereocontrol in the Palladium-Catalyzed [4+2] Annulation of Cyclopropenes with Benzosilacyclobutanes.

A novel and unusual palladium-catalyzed [4+2] annulation of cyclopropenes with benzosilacyclobutanes is reported. This reaction occurred through chemoselective Si-C(sp ) bond activation in synergy with ring expansion/insertion of cyclopropenes to form new C(sp )-C(sp ) and Si-C(sp ) bonds. An array of previously elusive bicyclic skeleton with high strain, silabicyclo[4.

Palladium-catalyzed olefination of aryl/alkyl halides with trimethylsilyldiazomethane via carbene migratory insertion.

The direct olefination of aryl/alkyl halides with trimethylsilyldiazomethane (TMSD) as a C1- or C2-unit was achieved successfully via a metal carbene migratory insertion process, which offered a new access to afford (E)-vinyl silanes and (E)-silyl-substituted α,β-unsaturated amides in good yields and high chemoselectivity.