PYRIDINOPHANE CRYPTAND HOSTS WITH DICOPPER(I) OR DICOPPER(II) PREFERENCES

A hexaimino pyridinophane cryptand, L4 derived by [2 + 3] Schiff base condensation of tris-2-ethylamino amine (tren) with diformylpyridine fails to host Cu(II) but accommodates dicopper(I) with reasonable oxidative stability; the octaamino derivative, L5, functions as a good host for dicopper(II). A single crystal X-ray structure determination was carried out on [Cu2L4](ClO4)2CH2Cl2, monoclinic, unit cell dimensions, a = 27.256(8), b = 10.970(3), c = 18.941(6) angstrom, beta = 128.37(3)-degrees, U = 4440(2) angstrom3. Each Cu(I) ion is coordinated to three imino donors and shows weaker interactions with other donors. The Cu(I)-Cu(I) distance is 3.038 angstrom.