Synthesis and Characterization of [Zn(SEt)Et]10, Formed via Insertion of Sulfur into Zn-C Bonds: A New Class of Wurtzite-like Cluster Framework

Abstract

Abstract : The reaction of a toluene solution of ZnEt2 with one equivalent of sulfur (1/8 S8) results in dissolution of the sulfur to form a colorless solution. After addition of n-pentane and cooling, colorless crystals of Zn10(SEt)10Et10 were isolated and characterized by a variety of spectroscopic characterization techniques and by single-crystal X-ray diffraction. Crystallographic data for Zn10(SEt)10Et10 at 293K: space group P(bar 1), a = 12. 010 (2)A, b = 14.739 (3)A, c = 20.327 (4)A, a = 99.93 (3) deg, beta = 91.62 (3) deg, gamma = 107.79 (3) deg, V = 3362.2 (11) A3, Z = 2, d(calc) = 1.636 g/cu cm, R = 9.41%, Rw = 9.00%. Although the crystal deteriorated during data collection, the structural data show that Zn10(SEt)10Et10 exhibits a unique wurtzite-like ZnS core rather than a sphalerite-like core which is more common to zinc and cadmium alkylthiolate clusters. Thermal decomposition of Zn10(SE)10Et10 was studied by diffraction methods, microscopy, thermal analysis and elemental analysis. These data are consistent with the formation of a crystalline, cubic (sphalerite) ZnS at low temperatures, 250 deg C, providing evidence that the structure of the molecular precursor does not direct the crystallization of a particular polymorph on solid-state thermolysis in this system.