Pt/Pd and I/Br Isostructural Exchange Provides Formation of C–I···Pd, C–Br···Pt, and C–Br···Pd Metal-Involving Halogen Bonding

Complexes trans-[MCl2(NCNMe2)2] (M = Pt 1, Pd 2) were cocrystallized with CHBr3 and CHI3, forming 1:2 adducts isomorphic with previously reported trans-[PtCl2(NCNMe2)2]·2CHI3. In all cases, the C–X···M (X = Br, I; M = Pd, Pt) metal-involving halogen bonding together with numerous chloride-halomethane halogen and hydrogen bonds were identified by single-crystal XRD experiments. Further DFT calculations and topological analysis of the electron density distribution within the framework of QTAIM method at the M06/DZP-DKH level of theory confirmed the existence of these interactions and their noncovalent nature. Estimated energies of such contacts vary from 1.6 to 3.1 kcal/mol