Catalytic Enantioselective Hetero-dimerization of Acrylates and 1,3-Dienes
作者:Stanley M. Jing、Vagulejan Balasanthiran、Vinayak Pagar、Judith C. Gallucci、T. V. RajanBabu
DOI:10.1021/jacs.7b10055
日期:2017.12.13
counterion, and solventeffects uncovered during the course of these investigations show a unique role of a possible cationic Co(I) intermediate in these reactions. The rational evolution of a mechanism-based strategy that led to the eventual successful outcome and the attendant support studies may have further implications for the expanding use of low-valent group 9 metal complexes in organic synthesis
Synthesis of 12-vertex mixed ligand closo-cobaltacarborane complexes and molecular structure of [3,3-(Ph2P(CH2)2PPh2)-3-Cl-closo-3,1,2-CoC2B9H11]
作者:A. P. Tyurin、A. F. Smol’yakov、F. M. Dolgushin、I. A. Godovikov、I. T. Chizhevsky
DOI:10.1007/s11172-013-0280-1
日期:2013.8
A reaction of complexes CoCl2(dppe) (dppe is the 1,2-bis(diphenylphosphino)ethane) or CoCl2(dppp) (dppp is the 1,3-bis(diphenylphosphino)propane) with [K][7,8-nido-C2B9H12] upon reflux in benzene led to the mixed ligand closo-cobaltacarboranes [3,3-(Ph2P(CH2) n PPh2)-3-Cl-closo-3,1,2-CoIIIC2B9H11] (n = 2 and 3, respectively) in moderate yields (34 and 16%). The structure of the 18-electron complexes in solution and the solid state was studied by NMR and IR spectroscopy, the structure in the case of the closo-complex with dppe-ligand was confirmed by X-ray crystallography.
Cobalt-catalysed asymmetric hydrovinylation of 1,3-dienes
作者:Yam N. Timsina、Rakesh K. Sharma、T. V. RajanBabu
DOI:10.1039/c5sc00929d
日期:——
of bidentate 1,n-bis-diphenylphosphinoalkane-CoCl2 complexes Cl2Co[P~P]} and Me3Al or methylaluminoxane, acyclic (E)-1,3-dienes react with ethylene (1 atmosphere) to give excellent yields of hydrovinylation products. The regioselectivity (1,4- or...
Alkylation of a tetrahedral cobalt(II)–dichloro complex bearing a sterically demanding and electron-donating diphosphine chelate gave a corresponding dialkyl-complex, which is the first coordinatively unsaturated cobalt(II)-(diphosphine)(dialkyl) complex isolated and characterized by X-ray analysis. This complex is expected to serve as a model intermediate in the cobalt(II)-catalyzed Heck-type reactions.
通过对带有立体要求高和电子捐赠型二膦螯合物的四面体钴(II)-二氯络合物进行烷基化,得到了相应的二烷基络合物,这是分离出的首个配位不饱和钴(II)-(二膦)(二烷基)络合物,并通过 X 射线分析对其进行了表征。该配合物有望成为钴(II)催化的赫克型反应的中间体模型。