Beschreibung:
<jats:p>The nature of the interaction between chloromethanes CH<jats:sub>4–<jats:italic>n</jats:italic></jats:sub>Cl<jats:italic><jats:sub>n</jats:sub></jats:italic>and Pt(II) complexes has been studied by high‐pressure X‐ray diffraction and infrared spectroscopy in combination with DFT calculations. In case of electron rich complexes such as d<jats:sup>8</jats:sup>‐Pt(btz‐<jats:italic>N</jats:italic>,<jats:italic>N</jats:italic>′)(phenyl)<jats:italic>L</jats:italic>with<jats:italic>L</jats:italic>= phenyl, Cl, Br and btz = 2,2′‐Bi‐5,6‐dihydro‐4<jats:italic>H</jats:italic>‐1,3‐thiazine stable chloroform adducts with bridging hydrogen atoms in the η<jats:sup>1</jats:sup>(C–H)Pt moieties were isolated which display highly activated C–H bonds. This activation is a consequence of a pronounced Pt(d<jats:sub><jats:italic>z</jats:italic>²</jats:sub>)→σ*(C–H) back donation and is signaled by large red‐shifts of the isolated<jats:italic>ν</jats:italic><jats:sub>is</jats:sub>(C–H) stretching modes. The extent of the C–H bond activation and covalent Pt–H bond formation in the η<jats:sup>1</jats:sup>(C–H)Pt moieties is thereby controlled by (<jats:italic>i</jats:italic>) the σ/π donor capabilities of the ligands<jats:italic>L</jats:italic>, (<jats:italic>ii</jats:italic>) the orientation of the coordinating C–H bond with regard to the Pt(d<jats:sub><jats:italic>z</jats:italic>²</jats:sub>) orbital and (<jats:italic>iii</jats:italic>) the applied pressure.</jats:p>