Lewis-base adducts of group 11 metal(I) compounds.: LXXVI structural studies in the copper(I) halide:norbornadiene system

The structural characterizations of some copper(I) halide (CuX) adducts with norbornadiene ('nbd') are recorded. CuCl : nbd (1:1)(4) (a redetermination), (2:1)(2(infinity|infinity)), are systems both based around Cu4Cl4 'cubane'-type cluster arrays. CuBr : nbd (7:3)((infinity|infinity))(0.5 MeOH), a complex polymer with 3-symmetry, is believed to be the complex previously described as an adduct of 2: 1 stoichiometry. Attempts to obtain an iodide counterpart have resulted in the definition of an ephemeral adduct CuI : MeCN (3:2)((infinity|infinity)). 0.5 C7H8 in which, remarkably, the nbd is uncoordinated; the complex is a polymer, related to the [AgX(quinoline)]((infinity|infinity)) (X = Cl, Br) 'saddle' polymer.