Synthesis and characterization of heteroleptic cyclometalated divalent osmium Os[P(C6H5)3]2(CO)(N∩C−)Cl complexes

• trans-cis-cis-Os[P(C6H5)3]2(CO)2Cl2 can be prepared from K2OsCl6 and P(C6H5)3.
• Os[P(C6H5)3]2(CO)2Cl2 precursor reacts with bidentate N∩CH ligands.
• Luminescent Os[P(C6H5)3]2(CO)(N∩C −)Cl chelates have been characterized.

Simple synthetic procedure, reaction of Os[P(C6H5)3]2(CO)2Cl2 with 2-phenylpyridine (or other similar N∩CH chelating ligands) in boiling 2-(2-ethoxyethoxy)ethanol solution leads to Os[P(C6H5)3]2(CO)(N∩C−)Cl complexes. Structures of the obtained species have been elucidated by means of 31P NMR and FT-IR techniques as well as elemental analysis data. The UV–vis absorption and emission properties of the newly synthesized complexes reveal the MLCT character of their lowest singlet and triplet excited states.

Simple reaction of K2OsCl6 with P(C6H5)3 performed in refluxing DMF solution leads to quantitative formation of trans-cis-cis-Os[P(C6H5)3]2(CO)2Cl2. In reactions with different bidentate N∩CH ligands the synthesized Os[P(C6H5)3]2(CO)2Cl2 precursor can be further converted to luminescent Os[P(C6H5)3]2(CO)(N∩C−)Cl chelates.Figure optionsDownload as PowerPoint slide