Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
Inorg Chem. 2011 Dec 19;50(24):12359-73. doi: 10.1021/ic201161q. Epub 2011 Jul 27.
The fields of sulfur-nitrogen-fluorine chemistry and noble-gas chemistry have been significantly extended by the syntheses and characterizations of four new Xe-N-bonded cations derived from N≡SF(3). The adduct-cation, F(3)S≡NXeF(+), has provided the entry point to a significant chemistry through HF solvolysis of the coordinated N≡SF(3) ligand and HF-catalyzed and solid-state rearrangements of F(3)S≡NXeF(+). The HF solvolyses of [F(3)S≡NXeF][AsF(6)] in anhydrous HF (aHF) and aHF/BrF(5) solutions yield the F(4)S═NXe(+) cation, which likely arises from an HF-catalyzed mechanism. The F(4)S═NXe(+) cation, in turn, undergoes HF displacement to form F(4)S═NH(2)(+) and XeF(2), as well as HF addition to the S═N bond to form F(5)SN(H)Xe(+). Both cations undergo further solvolyses in aHF to form the F(5)SNH(3)(+) cation. The F(4)S═NXe(+) and F(4)S═NH(2)(+) cations were characterized by NMR spectroscopy and single-crystal X-ray diffraction and exhibit high barriers to rotation about their S═N double bonds. They are the first cations known to contain the F(4)S═N- group and significantly extend the chemistry of this ligand. The solid-state rearrangement of [F(3)S≡NXeF][AsF(6)] at 22 °C has yielded [F(4)S═NXe][AsF(6)], which was characterized by Raman spectroscopy, providing the first examples of xenon bonded to an imido nitrogen and of the F(4)S═N- group bonded to a noble-gas element. The rearrangement of [F(3)S≡NXeF][AsF(6)] in a N≡SF(3) solution at 0 °C also yielded [F(4)S═NXe−N≡SF(3)][AsF(6)], which represents a rare example of a N−Xe−N linkage and the first to be characterized by X-ray crystallography. Solvolysis of N≡SF(3) in aHF was previously shown to give the primary amine F(5)SNH(2), whereas solvolysis in the superacid medium, AsF(5)/aHF, results in amine protonation to give [F(5)SNH(3)][AsF(6)]. Complete structural characterizations were not available for either species. Isolation of F(5)SNH(2)·nHF from the reaction of N≡SF(3) with HF has provided a structural characterization of F(5)SNH(2) by Raman spectroscopy. Crystal growth by sublimation of F(5)SNH(2)·nHF at -30 to -40 °C has resulted in the X-ray crystal structure of F(5)SNH(2)·2[F(5)SNH(3)][HF(2)]·4HF and structural characterizations of F(5)SNH(2) and F(5)SNH(3)(+). The redox decomposition of [F(4)S═NXe−N≡SF(3)][AsF(6)] in N≡SF(3) at 0 °C generated Xe, cis-N(2)F(2), and [F(3)S(N≡SF(3))(2)][AsF(6)].
通过合成和表征四个源自 N≡SF(3) 的新型 Xe-N 键合阳离子，硫-氮-氟化学和稀有气体化学领域得到了显著扩展。加合物阳离子 F(3)S≡NXeF(+) 通过 HF 溶剂解配位的 N≡SF(3) 配体以及 HF 催化和固态重排 F(3)S≡NXeF(+)，为重要的化学提供了切入点。[F(3)S≡NXeF][AsF(6)] 在无水 HF(aHF)和 aHF/BrF(5)溶液中的 HF 溶剂解反应生成 F(4)S═NXe(+) 阳离子，该阳离子可能是 HF 催化机制的产物。F(4)S═NXe(+) 阳离子继而发生 HF 取代形成 F(4)S═NH(2)(+) 和 XeF(2)，以及 S═N 键的 HF 加成形成 F(5)SN(H)Xe(+)。这两种阳离子在 aHF 中进一步发生溶剂解反应，形成 F(5)SNH(3)(+) 阳离子。F(4)S═NXe(+) 和 F(4)S═NH(2)(+) 阳离子通过 NMR 光谱和单晶 X 射线衍射进行了表征，它们在 S═N 双键上的旋转存在很高的能垒。它们是已知的第一个含有 F(4)S═N-基团的阳离子，极大地扩展了该配体的化学性质。[F(3)S≡NXeF][AsF(6)] 在 22°C 下的固态重排生成了[F(4)S═NXe][AsF(6)]，这通过拉曼光谱进行了表征，为 Xe 与亚胺氮键合以及 F(4)S═N-基团与稀有气体元素键合提供了首例。[F(3)S≡NXeF][AsF(6)]在 0°C 的 N≡SF(3)溶液中的重排也生成了[F(4)S═NXe−N≡SF(3)][AsF(6)]，这代表了 N−Xe−N 键的罕见实例，也是第一个通过 X 射线晶体学进行表征的实例。之前的研究表明，N≡SF(3)在 aHF 中的溶剂解反应会生成仲胺 F(5)SNH(2)，而在超强酸介质 AsF(5)/aHF 中的溶剂解反应会导致胺质子化，生成[F(5)SNH(3)][AsF(6)]。这两种物质的完整结构特征都没有得到。HF 与 N≡SF(3)反应得到 F(5)SNH(2)·nHF，从该物质中分离出 F(5)SNH(2)，通过拉曼光谱对 F(5)SNH(2)进行了结构表征。F(5)SNH(2)·nHF 通过升华在-30 至-40°C 下结晶生长，得到了 F(5)SNH(2)·2[F(5)SNH(3)][HF(2)]·4HF 的 X 射线晶体结构以及 F(5)SNH(2)和 F(5)SNH(3)(+)的结构特征。[F(4)S═NXe−N≡SF(3)][AsF(6)]在 0°C 的 N≡SF(3)中的还原分解生成了 Xe、顺式-N(2)F(2)和[F(3)S(N≡SF(3))(2)][AsF(6)]。
