Versatility of Dithiophosphates in the Syntheses of Copper(I) Complexes with Bis(diphenylphosphino)alkanes: Abstraction of Chloride from Dichloromethane

Reactions of [Cu(CH3CN)4]X (X = PF6, BF4) with bis(diphenylphosphino)methane (dppm = Ph2PCH2PPh2) and
ammonium dialkyldithiophosphates, (NH4)[S2P(OR)2] (R = Et, iPr), yield a series of novel CuI polynuclear complexes,
trinuclear [Cu3(μ-dppm)3(μ3-Cl){S2P(OEt)2}] (PF6) 1 and [Cu3(μ-dppm)2{S2P(OR)2}2](PF6) (R = Et, 2; iPr, 3),
tetranuclear [Cu4(μ-dppm)2 {S2P(OEt)2}4] 4, and hexanuclear [Cu6(μ-dppm)2(μ4-Cl){S2P(OiPr)2}4](BF4) 5. Similarly,
the reaction of [Cu2(μ-L−L)2(CH3CN)2](PF6)2 (L−L, dppm, dppe = Ph2PCH2CH2PPh2) with (NH4)[S2P(OR)2] yields
dinuclear [Cu2(μ-dppm)2{S2P(OR)2}2] 6 (R= iPr, 6A; Et, 6B), trinuclear [Cu3(μ-dppe)3(μ-Cl)2{S2P(OiPr)2}] 9, and
polymeric [Cu(μ2-dppe){S2P(OR)2}]n (R = Et, 7; iPr, 8) complexes. The formation of 1 and 5 involved the abstraction
of chloride from dichloromethane when the Cu/S2P(OR)2 ratio exceeded 1, but when ratio was 1:1, no Cl abstraction
occurred, as in compound 4. Compound 9, however, was obtained as a 12% byproduct in the synthesis of 8 using
a 1:1:1 ratio of Cu/dppe/S2P(OiPr)2. The chloride binds to Cu atoms in a μ3-Cl mode by capping one face of the
Cu3 triangle of cluster 1. A μ4-Cl caps a single tetragonal face of the trigonal prism of cluster 5, and in the cluster
9, two chlorides bond in μ2-Cl modes. Both clusters 2 and 3 exhibit the μ3-S mode of bonding for dtp ligands. Only
cluster 5 exhibited close Cu···Cu contacts (2.997−3.0238 Å). All of compounds were characterized by single-crystal X-ray diffraction and pertinent crystallographic data for 1, 5, and 9 are are follows: (1) C79H76ClCu3F6O2P8S2,
triclinic, P1̄, a = 11.213(1) Å, b = 14.142(1) Å, c = 25.910(2) Å, α = 95.328(2)°, β = 99.594(2)°, γ = 102.581(2)°, V = 3918.2(6) Å3, Z = 2; (5) C74H100BClCu6F4O8P8S8, monoclinic, P21/n, a = 25.198(4) Å, b = 15.990(3)
Å, c = 25.421(4) Å, β = 106.027(3)°, V = 9845(3)Å3, Z = 4; (9) C84H86Cl2Cu3O2P7S2, monoclinic, C2/c, with a
= 24.965(3) Å, b = 17.058(2) Å, c = 20.253(2) Å, β = 95.351(4)°, V = 8587.4(17)Å3, Z = 4.