208348-94-1Relevant academic research and scientific papers
Intra- and inter-molecular carboranyl C-H ... N hydrogen bonds in pyridyl-containing ortho-carboranes
Alekseyeva, Elena S.,Batsanov, Andrei S.,Boyd, Lynn A.,Fox, Mark A.,Hibbert, Thomas G.,Howard, Judith A.K.,MacBride, J.A. Hugh,Mackinnon, Angus,Wade, Kenneth
, p. 475 - 482 (2003)
Four C-substituted derivatives of ortho-carborane, 1-R-1,2-C2B10H11, where R = 2′-pyridyl (1), 2′-picolyl (2), 5′-bromo-2′-pyridyl (3) or 3′-pyridyl (4) have been prepared using adaptations of standard procedures, and structurally characterised by single crystal X-ray diffraction studies in an exploration of C-H ... N hydrogen bonding effects involving their carborane CH units. Calculations at the MP2/6-31G* level of theory were used to assess the strength of the hydrogen bonding detected, and calculated NMR shifts at the GIAO-B3LYP/6-311G* level were compared with measured C-H shifts to show that intramolecular C H ... N hydrogen bonding persisted in solution in the case of compound 1. The value of IR C-H stretching frequencies for probing hydrogen bonding in these systems was also studied. An unsuccessful attempt to convert compound 3 into a macrocyclic species (C2B10H10C5H3N)3 in which three ortho-carborane units are linked through 2,5-disubstituted pyridine rings is also described.
Preparation, structure, and olefin polymerization behavior of a picolyl-functionalized carborane nickel(II) complex
Wang, Xin,Jin, Guo-Xin
, p. 6319 - 6322 (2004)
The picolyl-functionalized o-carborane ligand CabNH (1; Cab NH = 1-(2′-picolyl)-o-carborane) was prepared from the monolithium carborane LiHC2B10H10 (=LiCab) and picolyl chloride (2-CH2ClC5H5N). 1 was lithiated with n-BuLi and then reacted with Ni(PPh3) 2Cl2 to give the mononuclear Ni complex [(Cab N)2]Ni (2). 2 was characterized by IR and NMR spectroscopy and elemental analysis. In addition, an X-ray structure analysis was performed on the complex, where the potential C,N-chelate ligand 1 was found to coordinate in a bidentate mode. The carborane complex 2 shows moderate catalytic activities of up to 3 × 106 g of PNB (mol of Ni)-1 h-1 for the addition polymerization of norbornene in the presence of methylaluminoxane (MAO) as cocatalyst. Catalytic activities, molecular weights, and molecular weight distributions of polynorbornene (PNB) have been investigated under the various reaction conditions.
