New Umpolung Catalysts: Reactivity and Selectivity of Terpenol-Based Lithium Phosphonates in Enantioselective Benzoin-Type Couplings
作者:Anca Gliga、Helge Klare、Maria Schumacher、Francis Soki、Jörg M. Neudörfl、Bernd Goldfuss
DOI:10.1002/ejoc.201001295
日期:2011.1
Two newclasses of terpenol-based lithium phosphonates, i.e. phenylfenchyl phosphonates and 2,2'-biphenyldiylbis(terpenyl) phosphonates, are employed as umpolung catalysts for the enantioselective cross benzoin coupling. The structural characteristics of the phosphonates were investigated by means of X-ray, 31 P-NMR analyses as well as DFT computations. The chiral lithium phosphonates were found to