School of Chemistry, University of Southampton, Southampton SO17 1BJ, UK.
Dalton Trans. 2013 Jun 21;42(23):8364-74. doi: 10.1039/c3dt50743b. Epub 2013 Apr 24.
Reaction of SnF2 in MeOH with the appropriate neutral N- or O-donor ligands produces [SnF(2,2'-bipy)]2SnF6, [SnF(1,10-phen)]2SnF4 and [SnF2(L)] L = Me3PO, dmso or pyNO). The X-ray structures of [SnF(2,2'-bipy)]2SnF6, [SnF(1,10-phen)]2SnF4 and [SnF2(dmso)], reveal trigonal pyramidal Sn(II) cores with longer fluorine bridges completing distorted 5- or 6-coordination. Attempts to prepare SnF2 adducts with various phosphine or diphosphine ligands in MeCN failed, whilst in CH2Cl2 solution complex reactions involving the solvent occurred. The NHC, 1,3-(2,6-di-isopropylphenyl)imidazol-2-ylidene (IDiPP) and SnF2 produced the imidazolium salt, [IDiPPH]SnF3, the crystal structure of which revealed the first example of a discrete trifluorostannate(II) ion. In contrast, diphosphine complexes of tin(II) chloride formed readily, including [SnCl2{Me2P(CH2)2PMe2}], [SnCl2{o-C6H4(PMe2)2}], [SnCl2{o-C6H4(PPh2)2}] and [(SnCl2)2(μ-Ph2P(CH2)2PPh2)], which were characterised by X-ray crystallography. The structures of [SnCl2{Me2P(CH2)2PMe2}] and [SnCl2{o-C6H4(PMe2)2}] reveal chloride-bridged dimers, but [SnCl2{o-C6H4(PPh2)2}], although also dimeric, has very asymmetric diphosphine coordination best described as κ(1). The structures of [(SnCl2)2(μ-Ph2P(CH2)2PPh2)] and of [SnCl{o-C6H4(AsMe2)2}]SnCl3 reveal trigonal pyramidal cores, but with longer Sn···Cl bridges affording polymeric structures. The synthesis of [SnCl2(R3EO)2] (R = Ph, E = P or As; and R = Me, E = P) are also reported, along with the structure of [SnCl2(Me3PO)2], which contains distorted tetragonal pyramidal Sn(II) coordination. X-ray structures are also reported for [(PMe3)2CH2][SnCl3]2 and [Ph2P(H)(CH2)2P(H)Ph2][SnCl3]2, obtained as by-products from the attempts to synthesise phosphine complexes, as well as [(o-C6H4(PMe2)2CH2]I2. All complexes were characterised by microanalysis, IR and multinuclear NMR spectroscopy ((1)H, (19)F{(1)H}, (31)P{(1)H } and, where solubility allowed, (119)Sn). Comparisons are drawn with corresponding Sn(IV) and Ge(II) complexes.
SnF2 在 MeOH 中与适当的中性 N 或 O-供体配体反应生成 [SnF(2,2'-bipy)]2SnF6、[SnF(1,10-phen)]2SnF4 和 [SnF2(L)]（L = Me3PO、dmso 或 pyNO）。[SnF(2,2'-bipy)]2SnF6、[SnF(1,10-phen)]2SnF4 和 [SnF2(dmso)]的 X 射线结构揭示了具有更长氟桥的扭曲的 5 或 6 配位的三角双锥 Sn(II)核。试图在 MeCN 中用各种膦或双膦配体制备 SnF2 加合物的尝试失败了，而在 CH2Cl2 溶液中则发生了涉及溶剂的复杂反应。NHC、1,3-(2,6-二异丙基苯基)咪唑-2-亚基（IDiPP）和 SnF2 产生了咪唑翁盐 [IDiPPH]SnF3，其晶体结构揭示了离散的三氟锡酸盐(II)离子的第一个例子。相比之下，锡(II)氯化物的双膦配合物很容易形成，包括 [SnCl2{Me2P(CH2)2PMe2}]、[SnCl2{o-C6H4(PMe2)2}]、[SnCl2{o-C6H4(PPh2)2}] 和 [(SnCl2)2(μ-Ph2P(CH2)2PPh2)]，它们均通过 X 射线晶体学进行了表征。[SnCl2{Me2P(CH2)2PMe2}] 和 [SnCl2{o-C6H4(PMe2)2}] 的结构揭示了氯化物桥联的二聚体，但 [SnCl2{o-C6H4(PPh2)2}] 尽管也是二聚体，但具有非常不对称的双膦配位，最好描述为 κ(1)。[(SnCl2)2(μ-Ph2P(CH2)2PPh2)] 和 [SnCl{o-C6H4(AsMe2)2}]SnCl3 的结构揭示了三角双锥核，但更长的 Sn···Cl 桥提供了聚合物结构。还报道了 [SnCl2(R3EO)2]（R = Ph，E = P 或 As；和 R = Me，E = P）的合成，以及 [SnCl2(Me3PO)2] 的结构，其中包含扭曲的四方锥 Sn(II)配位。还报道了 [(PMe3)2CH2][SnCl3]2 和 [Ph2P(H)(CH2)2P(H)Ph2][SnCl3]2 的 X 射线结构，这些结构是在试图合成膦配合物时作为副产物获得的，以及 [(o-C6H4(PMe2)2CH2]I2。所有配合物均通过微量分析、IR 和多核 NMR 光谱（(1)H、(19)F{(1)H}、(31)P{(1)H}和在溶解度允许的情况下（119)Sn）进行了表征。并与相应的 Sn(IV)和 Ge(II)配合物进行了比较。
