Formation, crystal and molecular structures of heteroleptic zinc(II) tri- tert-butoxysilanethiolates with ZnNO 2S 2 and ZnN 2S 2 coordination pattern

Abstract

Five zinc tri- tert-butoxysilanethiolates containing heterocyclic, aromatic bases coordinated to zinc ion were synthesized. All obtained complexes are monomeric with ZnS 2NO 2 or ZnS 2N 2 core and formula: Zn(SSi(OBu t ) 3) 2L, where L is α-picoline (pic), 2,4-lutidine (lut) or N-methylimidazole (meim) or Zn(SSi(OBu t ) 3) 2L 2 where L is pyridine (py) or N-methylimidazole. The complexes are formed in the two-stage synthesis. First zinc acetyloacetonate Zn(acac) 2 reacts with tri- tert-butoxysilanethiol with the formation of [Zn{μ-SSi(OBu t ) 3}(acac)] 2 [B. Becker, A. Dołęga, A. Konitz, W. Wojnowski, Polyhedron 20 (2001) 949]. Subsequent addition of heterocycle leads to decomposition of [Zn{μ-SSi(OBu t ) 3}(acac)] 2 and complexes Zn(SSi(OBu t ) 3) 2L or Zn(SSi(OBu t ) 3) 2L 2 are formed. Crystal structure determinations of the obtained complexes reveal distorted tetrahedral (Zn(SSi(OBu t ) 3) 2L 2) or bipyramidal (Zn(SSi(OBu t ) 3) 2L) coordination of zinc atom. In the case of Zn(SSi(OBu t ) 3) 2L the immediate environment of zinc atom consists of two thiolate sulfur atoms, aromatic nitrogen and two oxygen atoms from tert-butoxy groups of tri- tert-butoxysilanethiolate completing coordination sphere.