Solution and solid-state studies of hydrogen and halogen bonding with N-heterocyclic carbene supported nickel(II) fluoride complexes.

Nickel fluoride complexes of the type [Ni(F)(L)(Ar)] (L = phosphine, Ar = fluorinated arene) are well-known to form strong halogen and hydrogen bonds in solution and in the solid state. A comprehensive study of such non-covalent interactions using bis(carbene) complexes as acceptors and suitable halogen and hydrogen bond donors is presented. In solution, the complex [Ni(F)(iPrIm)(CF)] forms halogen and hydrogen bonds with iodopentafluorobenzene and indole, respectively, which have formation constants () an order of magnitude greater than those of structurally related phosphine supported nickel fluorides.