Accessing cationic tetrylene-nickel(0) systems featuring donor-acceptor E-Ni triple bonds (E = Ge, Sn).

We describe facile synthetic methods for accessing linear cationic tetrylene nickel(0) complexes [ SiiP DippE·Ni(PPh 3 ) 3 ] + (E = Ge (4) and Sn (5); SiiP Dipp = [(iPr 3 Si)(Dipp)N] - ), which feature donor-acceptor E-Ni triple bonds. These species are readily accessed in a one-pot protocol, combining the bulky halo-tetrylenes SiiP DippECl (E = Ge (1) and Sn (2)), Ni(cod) 2 , PPh 3 , and Na[BAr F 4 ]. Given the diamagnetic nature of 4 and 5, they each contain a formal zero-valent Ni centre, making the E-M triple bonds in these complexes unique compared to previously reported metal tetrylidyne complexes, which typically feature covalent/ionic bonding. In-depth computational analyses of these species further support triple bond character in their E-Ni interactions.