Synthesis and characterization of perhalogenated triphenylphosphine-cymantrenes [(C5X5)Mn(CO)2(PPh3)] (X = F, Cl, Br) and [(C5HI4)Mn(CO)2(PPh3)]

Photolysis of the monohalocymantrenes [(C5H4X)Mn(CO)(3)] (X = F, Cl, Br, I) in the presence of triphenylphosphine yields the corresponding dicarbonyl complexes [(C5H4X)Mn(CO)(2)(PPh3)]. Stepwise metalation and electrophilic quench with (PhSO2)(2)NF, C2Cl6, C2HBr5 or I-2, respectively leads to [(C5H2F3)Mn(CO)(2)(PPh3)], [(C5X5)Mn(CO)(2)(PPh3)] (X=Cl, Br) and [(C5HI4)Mn(CO)(2)(PPh3)]. Further fluorination or iodination leads only to decomposition. However, lithiation of [(C5H2F3)Mn(CO)(2)(PPh3)] is possible and electrophilic quench with C2Cl6 leads finally to [(C5F3Cl2)Mn(CO)(2)(PPh3)]. The crystal structures of the tetra- and pentasubstituted compounds are reported. (C) 2021 Elsevier B.V. All rights reserved.