Syntheses, crystal structures, and characterizations of two novel cubane-like and double cubane-like molybdenum-copper-sulphur clusters {MoCu3S3(S2COEt)}(O)(Ph3P)3 and {Mo2Cu6S6(SCMe3)2}(O)2(Ph3P)4

Two novel heterometallic cubane-like and double cubane-like clusters, {MoCu3S3(S2COEt)}(O)(Ph3P)3I and {Mo2Cu6S6(SCMe3)2}(O)2(Ph3P)4II, were synthesized by reaction of {MoCu2S3}(O)(Ph3P)3 with CuS2COEt and CuSCMe3, respectively. ClusterI crystallized in the triclinic space group\(P\overline 1 \) (2) witha=12.766(6) A,b=22.904(5) A,c=10.522(3) A, α=99.86(2)°, β=109.68(2)°, γ=86.84(3)°,V=2854(2) A3,Z=2,R=0.049 for 6622 observed reflections (I>5σ(I)) and 410 variables. ClusterII crystallized in the triclinic space group\(P\overline 1 \) (2) with dimensionsa=14.212(4) A,b=14.725(5) A,c=12.396(8) A, α=110.32(4)°, β=90.40(5)°, γ=62.88(2)°,V=2129(2) A3,Z=1,R=0.039 for 6020 observed reflections (I>3σ(I)) and 461 variables. ClusterI consists of a neutral cubane-like molecule with the core {MoCu3S3(S2COEt)}2+, in which one corner of the cubane-like core is a novel triply bridging bidentate 1,1-dithiolato (xanthate, S2COEt−) ligand. ClusterII is a double cubane-like one, in which two cubane-like cores {MoCu3S3(SCMe3)}2+ are connected by two Cu-S bonds of the triply bridging monothiolato (SCMe 3 − ) ligand. Two different pathways of unit construction from a small heterometallic cluster {MoCu2S3}(O)(Ph3P)3 have been outlined. Comparisons of the selected bond lengths and bond angles for the cubane-like core {MoCu3S3X} (X=Cl−, Br−, S2COEt−, SCMe 3 − ) are given. Spectroscopic properties of the title clusters are also reported.