Self-assembly of the octanuclear cluster [Cu8(OH)10(NH2(CH2)2CH3)12]6+ and the one-dimensional N-propylcarbamate-linked coordination polymer {[Cu(O2CNH(CH2)2CH3)(NH2(CH2)2CH3)3](ClO4)}n

The reaction of Cu(ClO4)(2).6H(2)O and n-propylamine in methanol gives two high-nuclearity products of well-defined compositions. At amine concentrations greater than seven equivalents compared to copper ion concentration, the system fixes carbon dioxide from air to form the one-dimensional carbamate-bridged coordination polymer, {[Cu(mu(2)-O,O' O2CNH(CH2)(2)CH3)(NH2(CH2)(2)CH3)(3)](ClO4)} ({1-ClO4}(n)). Lower relative amine concentrations lead to the self-assembly of an octanuclear copper-amine-hydroxide cluster [Cu-8(OH)(10)(NH2(CH2)(2)CH3)(12)](6+) (2). Both compounds exhibit unique structures: {1-ClO4}(n), is the first mu(2)-O,O' mono-N-alkylcarbamate-linked coordination polymer and 2 is the largest copper-hydroxide-monodentate amine cluster identified to date. The crystal structures indicate that the size of the n-propyl group is probably crucial for directing the formation of these compounds. Magnetic susceptibility studies indicate very weak antiferromagnetic coupling for 1. The octanuclear cluster 2 displays slightly stronger net antiferromagnetic coupling, despite the presence of a number of Cu-O(H)-Cu angles below the value of about 97degrees that would normally be expected to yield ferromagnetic coupling.