COPPER(I) COMPLEXES WITH METAL-METAL (D10-D10) BOND - CRYSTAL AND MOLECULAR-STRUCTURES OF ADDUCTS OF TANTALOCENE TRIHYDRIDE WITH COPPER(I) IODIDE OF COMPOSITION - (ETA-5-C5H5)2TAH[MU-2-H)CU(MU-2-I)2CU(MU-2-H)]2HTA(ETA-5-C5H5)2, (ETA-5-C5H4BUT)2TAH(MU-2-H)2CU(MU-2-I)2CU(MU-2-H)2HTA(ETA-5-C5H4BUT)2.CH3CN AND (CU(MU-3-I).P[N(CH3)2]3)4

Title full: Copper(I) complexes with metal-metal (d10-d10) bond. Crystal and molecular structures of adducts of tantalocene trihydride with copper(I) iodide of composition: (η5-C5H5)2TaH[(μ 2-H)Cu(μ2-I)2Cu(μ2-H)] 2HTa(η5-C5H5)2, (η5-C5H4But)2 TaH(μ2-H)2Cu(μ2-I)2Cu( μ2-H)2HTa(η5-C5H 4But)2·CH3CN and {Cu(μ3-I)·P[N(CH3)2]3 }4. An interaction of copper(I) halogenides with tantalocene trihydride Cp′2TaH3 led to adducts of 2:1 (Cp = η5-C5H5) or 1:1 (Cp′ = C5H5But) composition. Structures of complexes (η5-C5H5)2TaH[(μ 2-H)Cu(μ2-I)2Cu(μ2-H)] 2TaH(η5-C5H5) (I) and (η5-C5H4But)2 TaH(μ2-H)2Cu(μ2-I)Cu(μ2 -H)2TaH(η5-C5H4 But)2 (III) were established by X-ray analysis. Crystals of I are monoclinic: a = 8.010, b = 11.032, c = 16.613 Å, γ = 105.1°, space group I2/m, Z = 2, R = 0.20. Crystals of III are monoclinic: a = 16.378(4), b = 16.968(4), c = 16.607(4) Å, γ = 113.57(3)°, space group P21/b, Z = 4, R = 0.031 (Rw = 0.031). In both complexes the Cu(μ2-I)2Cu moiety is bonded with tantalum atoms by one (I, Ta .... Cu = 2.788 Å) or two (III, Cu....Cu = 2.844 Å) hydrogen bridges. {A figure is presented} rhombs are not planar owing to the formation of the direct intermetal bonds between Cu(I) atoms (Cu....Cu distance is equal to 2.602 Å for I and 2.913 Å for III). The model of bonding in LnCu(μ2-I)2CuLn complexes has been proposed and the conditions of realization of the bond between transition metal atoms with a d10 electron shell are discussed. It is shown that the conditions of n = 2 and bulky ligand L are essential but insufficient, e.g. the 1:1 adduct of Cu(I) with bulky phosphine P(NMe2)3 is a tetramer [Cu(μ3-I)·P(NMe2)3]4 (V) without CuCu bonds. Crystals of V are monoclinic: a = 14.695(5), b = 14.999(5), c = 23.406(8) Å, space group P21/n, Z = 4, R = 0.039 (Rw = 0.040). © 1990.