Synthesis and characterization of the silver maleonitrilediselenolates and silver maleonitriledithiolates [K([2.2.2]-cryptand)]4[Ag4(Se2C2(CN)2)4], [Na([2.2.2]-cryptand)]4[Ag4(S2C2(CN)2)4].0.33MeCN, [NBu4]4[Ag4(S2C2(CN)2)4], [K([2.2.2]-cryptand)]3[Ag(Se2C2(CN)2)2].2MeCN, and [Na([2.2.2]-cryptand)]3[Ag(S2C2(CN)2)2

Reaction of AgBF(4), KNH(2), K(2)Se, Se, and 2.2.2]-cryptand in acetonitrile yields K(2.2.2]-cryptand)](4)Ag(4)(Se(2)C(2)(CN)(2))(4)] (1). In the unit cell of 1 there are four K(2.2.2]-cryptand)](+) units and a tetrahedral Ag(4) anionic core coordinated in mu(1)-Se, mu(2)-Se fashion by each of four mns ligands (mns = maleonitrilediselenolate, Se(2)C(2)(CN)(2)](2)(-)). Reaction of AgNO(3), Na(2)(mnt) (mnt = maleonitriledithiolate, S(2)C(2)(CN)(2)](2)(-)), and 2.2.2]-cryptand in acetonitrile yields Na(2.2.2]-cryptand)](4)Ag(4)(mnt)(4)].0.33MeCN (2). The Ag(4) anion of 2 is analogous to that in 1. Reaction of AgNO(3), Na(2)(mnt), and NBu(4)]Br in acetonitrile yields NBu(4)](4)Ag(4)(mnt)(4)] (3). The anion of 3 also comprises an Ag(4) core coordinated by four mnt ligands, but the Ag(4) core is diamond-shaped rather than tetrahedral. Reaction of K(2.2.2]-cryptand)](3)Ag(mns)(Se(6))] with KNH(2) and 2.2.2]-cryptand in acetonitrile yields K(2.2.2]-cryptand)](3)Ag(mns)(2)].2MeCN (4). The anion of 4 comprises an Ag center coordinated by two mns ligands in a tetrahedral arrangement. Reaction of AgNO(3), 2 equiv of Na(2)(mnt), and 2.2.2]-cryptand in acetonitrile yields Na(2.2.2]-cryptand)](3)Ag(mnt)(2)] (5). The anion of 5 is analogous to that of 4. Electronic absorption and infrared spectra of each complex show behavior characteristic of metal-maleonitriledichalcogenates. Crystal data (153 K): 1, P2/n, Z = 2, a = 18.362(2) A, b = 16.500(1) A, c = 19.673(2) A, beta = 94.67(1) degrees, V = 5941(1) A(3); 2, P4, Z = 4, a= 27.039(4) A, c = 15.358(3) A, V = 11229(3) A(3); 3, P2(1)/c, Z = 6, a = 15.689(3) A, b = 51.924(11) A, c = 17.393(4) A, beta = 93.51(1) degrees, V = 14142(5) A(3); 4, P2(1)/c, Z = 4, a = 13.997(1) A, b = 21.866(2) A, c = 28.281(2) A, beta = 97.72(1) degrees, V = 8578(1) A(3); 5, P2/n, Z = 2, a = 11.547(2) A, b = 11.766(2) A, c = 27.774(6) A, beta = 91.85(3) degrees, V = 3772(1) A(3).