Soran Albert, Breunig Hans J, Lippolis Vito, Arca Massimiliano, Silvestru Cristian
Facultatea de Chimie si Inginerie Chimica, Universitatea Babes-Bolyai, RO-400028, Cluj-Napoca, Romania.
Dalton Trans. 2009 Jan 7(1):77-84. doi: 10.1039/b811713f. Epub 2008 Oct 31.
The reaction of RLi [R = 2,6-{MeN(CH2CH2)2NCH2}2C6H3 ] with BiCl3 (1:1 molar ratio) afforded RBiCl2 (2). RBiBr2 (3) and RBiI2 (4) were obtained by halogen-exchange reactions from 2 . The organobismuth(III) dihalides containing the new steric demanding (N,C,N)-pincer ligand were characterized both in solution and solid state. The molecular structures of compounds were established by single-crystal X-ray diffraction. They all show a T-shaped CBiX(2) core, stabilized by two strong intramolecular N-->Bi interactions in trans positions to each other. The overall (N,C,N)BiX2 core exhibits a distorted square-pyramidal coordination geometry. The NMR studies provided evidences for the presence of internal nitrogen-bismuth coordination in solution too. DFT calculations were performed on the related species [2,6-(R(2)NCH(2))(2)C(6)H(3)]BiX(2) (R = H, Me; X = Cl, Br, I) in order to elucidate the bond nature and vibrational spectroscopic features of these compounds.
RLi [R = 2,6-{MeN(CH2CH2)2NCH2}2C6H3 ] 与BiCl3 (摩尔比1:1)反应生成RBiCl2 (2)。RBiBr2 (3) 和RBiI2 (4) 通过2的卤交换反应制得。含有新型空间位阻较大的 (N,C,N)-钳形配体的有机铋(III) 二卤化物在溶液和固态下均得到了表征。化合物的分子结构通过单晶X射线衍射确定。它们均显示出T形CBiX(2) 核心,通过两个相互处于反位的强分子内N→Bi相互作用得以稳定。整体的 (N,C,N)BiX2 核心呈现出扭曲的四方锥配位几何结构。核磁共振研究也为溶液中存在内部氮-铋配位提供了证据。对相关物种 [2,6-(R(2)NCH(2))(2)C(6)H(3)]BiX(2) (R = H, Me;X = Cl, Br, I)进行了密度泛函理论计算,以阐明这些化合物的键性质和振动光谱特征。