Alkynylated Palladium(II) and Platinum(II) Acyclic Diaminocarbene Complexes and Their Intramolecular Cyclization via <i>trans</i>-Chlorometalation

This study presents the synthesis of N-alkynylated acyclic diaminocarbene (ADC) complexes of palladium(II) and platinum(II) and their intramolecular cyclization via trans-chlorometalation. The reactions of propargylamines with bis-isocyanide complexes of Pd(II) and Pt(II) produced the desired ADC complexes in good yields. The NH,NH-diaminocarbene complexes were unstable in solution and underwent intramolecular cyclization into chlorometalated products. These findings provide a novel route to stable N-alkynylated ADC complexes with potential applications in catalysis and medicinal chemistry. The complexes synthesized exhibit promising structural and reactive properties suitable for further exploration.