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)₃ I and {Mo₂Cu₆S₆(SCMe₃)₂}(O)₂(Ph₃P)₄ II, were synthesized by reaction of {MoCu₂S₃}(O)(Ph₃P)₃ with CuS₂COEt and CuSCMe₃, respectively. ClusterI crystallized in the triclinic space group (2) witha=12.766(6) Å,b=22.904(5) Å,c=10.522(3) Å, =99.86(2)°, =109.68(2)°, =86.84(3)°,V=2854(2) ų,Z=2,R=0.049 for 6622 observed reflections (I>5(I)) and 410 variables. ClusterII crystallized in the triclinic space group (2) with dimensionsa=14.212(4) Å,b=14.725(5) Å,c=12.396(8) Å, =110.32(4)°, =90.40(5)°, =62.88(2)°,V=2129(2) ų,Z=1,R=0.039 for 6020 observed reflections (I>3(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 {MoCu₃S₃ X} (X=Cl^–, Br^–, S₂COEt^–, SCMe ₃ ^– ) are given. Spectroscopic properties of the title clusters are also reported.