| The chemistry of Mo(W)/Cu/S clusters have received much attention not only because of their diverse structural chemistry but also due to their potential applications in industrial catalytic systems and optoelectronic materials. Meanwhile, the chemistry of metal sulfide clusters with double cubanelike frameworks has been extensively investigated owing to their geometrical relevance to the active site structures of the P-cluster (Fe8S9) and FeMo-cofactor cluster (MoFe7S9) of nitrogenases. How to prepare those double cubanelike clusters has become a focus in the chemistry of clusters.In this thesis, we selected [Et4N][Tp*WS3] as starting material to react with AgSCN and AgSCN/NaSCN, and synthesized a double-[Tp*WS3]-containing W/S precursor [(Tp*WS2)2(μ-S2)] (2) and a double-W-containing W/S precursor [Et4N][Tp*W2S2 (μ-S)2(SCN)2] (3), respectively. Furthermore, precursor 2 was chosen to react with CuX (X= Cl, Br, I) and CuX (X = Cl, Br) in the presence of Et4NX (X = Cl, Br), and generated three neutral W/Cu/S clusters and two anionic W/Cu/S clusters. These compounds were characterized by elemental analysis, IR and single-crystal X-ray crystallography. The electrospray ionization (ESI) mass spectra and third-order nonlinear optical (NLO) properties of some compounds were also investigated.This dissertation was focused on:(1) The categories and syntheses of Mo(W)/S precursors, and general synthetic strategies of metal sulfide clusters with double cubanelike frameworks were reviewed.(2) Treatment of [Et4N][Tp*WS3] (1) with 2 equiv. of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS2)2(μ-S2)] (2). The dimeric structure of 2 can be viewed as two [Tp*WS2] fragments in which two W atoms are connected by one S22- dianion. Reaction of 1 with AgSCN and NaSCN generated an anionic compound [Et4N][Tp*W2S2 (μ-S)2(SCN)2] (3) in which two W atoms were linked by twoμ-S bridges.(3) Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH2Cl2 or CHCl3 formed three neutral W/Cu/S clusters [{Tp*W(μ3-S)3Cu3(μ-Cl)}2Cu(μ-Cl)2(μ7-Cl)(MeCN)]2 (4), [{Tp*W(μ3-S)3Cu3}2Br(μ-Br)2(μ4-Br)(MeCN)] (5), and [{Tp*W(μ3-S)3Cu3}2{Cu2(μ-I)4(μ3-I)2}] (6), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et4NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et4N][{Tp*W(μ3-S)3Cu3X}2(μ-X)2(μ4-X)] (7: X = Cl; 8: X = Br). Compounds 4–8 all possess unique halide-bridged double cubanelike frameworks. For 4, two [Tp*W(μ3-S)3Cu3]2+ dications are linked via aμ7-Cl- bridge, twoμ-Cl- bridges, and a [Cu(MeCN)(μ-Cl)2]+ bridge. For 5, one [Tp*W(μ3-S)3Cu3(MeCN)]2+ dication and one [Tp*W(μ3-S)3Cu3Br]+ cation are linked via aμ4-Br- and twoμ-Br- bridges. For 6, the two [Tp*W(μ3-S)3Cu3]2+ dications are bridged by a linear [(μ-I)2Cu(μ3-I)2Cu(μ-I)2]4+ species. For 7 and 8, two [Tp*W(μ3-S)3Cu3X]+ cations are linked by aμ4-X- and twoμ-X- bridges (X = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2, 4–8 in MeCN/CH2Cl2 were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique. Theγvalues of compounds 2, 4–8 are 1.25×10-31 esu (2), 3.12×10-31 esu (4), 2.63×10-31 esu (5), 2.77×10-31 esu (6), 2.76×10-31 esu (7) and 2.98×10-31 esu (8), respectively. Theγvalues of compounds 4–8 are 2.102.49 times larger than that of compound 2, while theγvalue of compound 2 is 11.7 times larger than [Et4N][Tp*WS3] (1.07×10-32 esu). |
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