[{Cu(en)(2)}(2)Re4Te4(CN)(12)]center dot 5H(2)O and [{Cu(en)(2)}(2)Re6Te8(CN)6]center dot 5H(2)O: Bonding of a transition-metal complex to a rhenium chalcocyanide cluster

The use of a cyano group of a transition-metal cluster complex to bond to a nother transition-metal complex has been realized in the syntheses of [{Cu( en)(2)}(2)Re4Te4(CN)(12)]. 5H(2)O (1) and [{Cu(en)(2)}(2)Re6Te8(CN)(6)]. 5H (2)O (2), (en = ethylenediamine). These compounds have been synthesized by the reaction of an aqueous solution of K-4[Re4Te4(CN)(12)]. 5H(2)O (for 1) or K-4[Re6Te8(CN)(6)] (for 2) with an ammonia solution of Cu(en)(2)Cl-2. In each compound, two Cu(en)(2) groups are bonded to the Re cluster through C u-N(cyanide) bonds. In compound 1, which contains a tetrahedral cluster cor e, the Cu(en)2 groups are necessarily bonded to cis cyano groups; in compou nd 2, which has an octahedral cluster core, they are bonded to trans cyano groups. Compound 1 crystallizes in the monoclinic space group C2/c with fou r formulas in unit cell of dimensions a = 18.9077(10), b = 15.4841(8), c = 14.4483(8) Angstrom, beta = 95.124(1)degrees, and V = 4213.1(4) Angstrom (3 ) (T = 153 K); compound 2 crystallizes in the triclinic space group P (1) o ver bar with one formula in a unit cell of dimensions a = 9.4906(3), b = 10 .6529(4), c = 12. 6252(5) Angstrom, alpha = 113.599(1)degrees, beta = 103.4 04(1)degrees, gamma = 92,659(1)degrees, and V = 1123.87(7) Angstrom (3) (T = 153 K).