Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China.
Dalton Trans. 2012 Jul 21;41(27):8447-54. doi: 10.1039/c2dt30860f. Epub 2012 May 30.
The reaction of [Ag(MeCN)(4)]ClO(4) with N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylenediamine (dppeda) in CH(2)Cl(2)/MeOH afforded an unexpected cationic binuclear complex Ag(2)(L(1))(2)(η,η-μ-ClO(4))(2)(2) (L(1) = N,N'-bis(diphenylphosphanylmethyl)-3H-4,5-dihydroimidazole-1-ium) (1). Compound 1 was also prepared in high yield from reactions of [Ag(MeCN)(4)]ClO(4) with N,N'-bis(diphenylphosphanylmethyl)ethylenediamine (bdppeda) in the presence of formaldehyde (HCHO) or formic acid (HCOOH). Analogous reactions of AgCl with bdppeda and HCHO resulted in the formation a neutral binuclear complex [Ag(2)(L(2))(2)(μ-Cl)(2)] (L(2) = N,N-bis(diphenylphosphanylmethyl)-tetrahydroimidazole) (2). Treatment of 1 with concentrated HCl gave rise to a partially anion-exchanged product Ag(2)(L(1))(2)(μ-Cl)(2)(2) (3). Compounds 1 and 3 have a similar cationic binuclear structure, in which a [Ag(2)(η,η-μ-ClO(4))(2)] or [Ag(2)(μ-Cl)(2)] ring is sandwiched by two in situ-formed cationic L(1) ligands. The L(1) ligand may be generated by the Ag(I)-assisted condensation reaction between bdppeda and HCHO or HCOOH. Compound 2 holds a neutral binuclear structure, in which a [Ag(2)(μ-Cl)(2)] ring is connected by two in situ-formed L(2) ligands from its top and bottom sites. The neutral ligand L(2) may be produced from another Ag(I)-assisted condensation reaction between bdppeda and HCHO. The in situ formation of the L(1) and L(2) ligands provides a new route to the N-heterocyclic diphosphine ligands, and an interesting insight into the coordination chemistry of their metal complexes.
[Ag(MeCN)(4)]ClO(4) 与 N,N,N',N'-四(二苯基膦基甲基)乙二胺(dppeda) 在 CH(2)Cl(2)/MeOH 中的反应得到了一种意想不到的阳离子双核配合物 Ag(2)(L(1))(2)(η,η-μ-ClO(4))(2)(2) (L(1) = N,N'-双(二苯基膦基甲基)-3H-4,5-二氢咪唑-1- 鎓) (1)。在存在甲醛(HCHO)或甲酸(HCOOH)的情况下，用 [Ag(MeCN)(4)]ClO(4)与 N,N'-双(二苯基膦基甲基)乙二胺(bdppeda)反应也以高产率制备了 1。AgCl 与 bdppeda 和 HCHO 的类似反应导致形成中性双核配合物[Ag(2)(L(2))(2)(μ-Cl)(2)] (L(2) = N,N-双(二苯基膦基甲基)-四氢咪唑) (2)。用浓 HCl 处理 1 得到部分阴离子交换产物Ag(2)(L(1))(2)(μ-Cl)(2)(2) (3)。化合物 1 和 3 具有相似的阳离子双核结构，其中[Ag(2)(η,η-μ-ClO(4))(2)]或[Ag(2)(μ-Cl)(2)]环被两个原位形成的阳离子 L(1)配体夹在中间。L(1)配体可能是由 bdppeda 和 HCHO 或 HCOOH 之间的 Ag(I)辅助缩合反应生成的。化合物 2 具有中性双核结构，其中[Ag(2)(μ-Cl)(2)]环通过两个从顶部和底部位置原位形成的 L(2)配体连接。中性配体 L(2)可能是由 bdppeda 和 HCHO 之间的另一个 Ag(I)辅助缩合反应产生的。L(1)和 L(2)配体的原位形成提供了一种获得 N-杂环二膦配体的新途径，并深入了解了它们的金属配合物的配位化学。
