Nickel complexes of phosphine-appended benzannulated boron heterocycles
- Author(s): Essex, LA
- Taylor, JW
- Harman, WH
- et al.
Published Web Locationhttps://doi.org/10.1016/j.tet.2019.02.047
© 2019 Elsevier Ltd We report the synthesis and characterization of two diphosphine nickel complexes containing 9-borafluorene (PBFlu, 9-(diisopropylphosphino)phenyl-9-borafluorene) and 9,10-dihydroboranthrene (B 2 P 2 , 9,10-bis(2-(diisopropylphosphino)phenyl)-9,10-dihydroboranthrene) cores. Metalation of PBFlu and B 2 P 2 with Ni(PPh 3 ) 4 leads to the monometallic complexes (PBFlu)Ni(PPh 3 ) and (B 2 P 2 )Ni, respectively. Cyclic voltammetry studies show a reversible redox event at ∼0.1 V and a quasi-reversible event at ca. −3 V versus ferrocene/ferrocenium for (B 2 P 2 )Ni while (PBFlu)Ni(PPh 3 ) features no reversible redox events. Electronic structure calculations were performed to provide further insight into the bonding in these complexes.