High Yield Synthesis and Characterization of Sn6(μ3-O)4(μ3-OSiMe3)4:  A Novel Main Group Cluster for the Support of Multiple Transition Metal Centers

• Published in: Journal of the American Chemical Society Vol. 119; no. 4; pp. 756 - 760
• Main Authors: Sita, Lawrence R, Xi, Rimo, Yap, Glenn P. A, Liable-Sands, Louise M, Rheingold, Arnold L
• Format: Journal Article
• Language: English
• Published: American Chemical Society 29.01.1997
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja963450t

A high yielding, highly reproducible synthesis of the novel main group cluster Sn6(μ3-O)4(μ3-OSiMe3)4 (2), which involves the thermolysis of bis[bis(trimethylsilanolato)tin] (4) at 180 °C, is reported. Spectroscopic and chemical analyses are fully consistent with the assigned structure of 2. A preliminary investigation of the reaction between this compound and Fe2(CO)9 reveals that the tin(II) centers of the former are capable of participating as 2e σ-donors in the formation of the Fe(CO)4 adducts, [{Fe(CO)4} Sn6(μ3-O)4(μ3-OSiMe3)4] (5) and [{Fe(CO)4}2Sn6(μ3-O)4(μ3-OSiMe3)4] (6). The assigned structures of 5 and 6 are confirmed by spectroscopic and crystallographic analyses and the latter reveal important information regarding the influence that the steric features of 2 have on the coordination sphere of transition metal centers that are ligated to it. Space-filling models also reveal that additional complexation to 2, 5, and 6 is sterically permitted. Together, these findings provide an important platform upon which a variety of future studies that utilize 2 as a new class of building block for the construction of mixed p−d metal compounds and materials can be based. Single crystals of 5 are (at 25 °C) monoclinic, space group P21 /n with a = 13.404(2) Å, b = 16.964(3) Å, c = 17.766(2) Å, β = 90.384(12)°, V = 4039.7(10) Å3, and Z = 4 (D calcd = 2.139 mg m-3; μ(Mo Kα) = 41.57 mm-1). Single crystals of 6·(0.7)1/2C6H6 are (at 23 °C) monoclinic, space group P21 /n with a = 11.804(2) Å, b = 17.489(3) Å, c = 23.222(2) Å, β = 97.146(9)°, V = 4756(1) Å3, and Z = 4 (D calcd = 2.089 mg m-3; μ(Mo Kα) = 38.41 mm-1).