Photochemically Induced Cyclometalations at Simple Platinum(II) Precursors

Photochemical cycloplatinations of 2-arylpyridines and related C perpendicular to N ligands, as well as terdentate heteroaromatic N perpendicular to N perpendicular to C, N perpendicular to C perpendicular to N, and N perpendicular to C perpendicular to C compounds, are demonstrated using (Bu4N)2[Pt2Cl6] or [PtCl2(NCPh)2] as precursors at room temperature. Mono-or bis-cyclometalated Pt(II) complexes with C perpendicular to N ligands are obtained depending on excitation wavelength and precursor. Monitoring experiments show that photoexcitation enables both the N-coordination and the subsequent C-H metalation. Photochemical synthetic protocols have been developed, which are advantageous with respect to the established thermal procedures and have allowed the synthesis of the first Pt(II) complexes with N perpendicular to C perpendicular to C ligands.

Automated summary

Photochemical cycloplatination reactions of 2-arylpyridines and terdentate heteroaromatic compounds have been demonstrated using (Bu4N)2[Pt2Cl6] or [PtCl2(NCPh)2] as precursors at room temperature. Depending on the excitation wavelength and precursor, mono- or bis-cyclometalated Pt(II) complexes with different ligands can be obtained. Photoexcitation enables the coordination of nitrogen and subsequent C-H metalation. The developed photochemical synthetic protocols have advantages over thermal procedures, allowing the synthesis of Pt(II) complexes with N perpendicular to C perpendicular to C ligands.