Synthesis and Structures of Oxo-Bridged Distannyl- and Digermyldirhenium Complexes

The reaction of Re2(CO)8(μ-SnPh2)2 (1) with NaOMe in methanol in the presence of Bun4NBr yielded
the salt [NBun4][Re2(CO)8{μ-Ph2SnO(Me)SnPh2}] (3). The anion of 3 contains a Ph2SnO(Me)SnPh2 ligand
formed by the addition of a [OMe]- group to the two bridging SnPh2 groups in 1. The bidentate ligand
bridges the two Re(CO)4 groups that are joined by a Re−Re single bond. The reaction of Re2(CO)8[μ-C(H)C(H)Bun](μ-H) with Ph3GeH and H2O in heptane solvent yielded the complex Re2(CO)8[μ-Ph2GeO(H)GePh2](μ-H) (4). The structure of 4 consists of two Re(CO)4 units bridged by a Ph2GeO(H)GePh2 ligand and a hydrido ligand that bridges the Re−Re bond. Compound 4 was deprotonated at
the OH group by treatment with [NBun4][OH] to give the salt [NBun4][Re2(CO)8(μ-Ph2GeOGePh2)(μ-H)] ([NBun4]·5). The three new compounds were characterized by IR, 1H NMR, and single-crystal X-ray
diffraction analyses. The electronic structures of 4 and 5 were probed by computations employing density
functional theory (ADF 2004.01, PW91).

八羰基二(μ-二苯基锡基)二铼(1)与甲醇钠（NaOMe）在甲醇溶剂中、四正丁基溴化铵（Bun4NBr）存在的条件下反应，得到盐类化合物[NBun4][Re₂(CO)₈{μ-Ph₂SnO(Me)SnPh₂}]（3）。该化合物3的阴离子中含有一个Ph₂SnO(Me)SnPh₂配体，该配体由反应物1中的两个桥联二苯基锡基团与甲氧基负离子（[OMe]⁻）加成生成。该双齿配体桥联两个通过Re-Re单键相连的Re(CO)₄单元。八羰基(μ-1-丁基亚乙烯基)(μ-氢)二铼与三苯基氢化锗（Ph₃GeH）和水在庚烷溶剂中反应，得到配合物Re₂(CO)₈[μ-Ph₂GeO(H)GePh₂](μ-H)（4）。化合物4的结构包含两个Re(CO)₄单元，二者分别由一个Ph₂GeO(H)GePh₂配体以及一个桥联Re-Re键的氢配体所桥联。化合物4的羟基（OH）经四正丁基氢氧化铵[NBun4][OH]处理后发生去质子化，得到盐类[NBun4][Re₂(CO)₈(μ-Ph₂GeOGePh₂)(μ-H)]（即[NBun4]·5）。上述三种新化合物均通过红外光谱（IR）、氢核磁共振谱（¹H NMR）以及单晶X射线衍射分析完成了表征。化合物4和5的电子结构则通过密度泛函理论（ADF 2004.01，PW91）进行了计算研究。