π Type Lithium Bond Interaction between Ethylene, Acetylene, or Benzene and Amido‐lithium

Abstract

Abstract The optimization geometries and interaction energy corrected by basis set super‐position error (BSSE) of the lithium bond complexes between ethylene, acetylene, or benzene and amido‐lithium have been calculated at the B3LYP/6‐311++G∗︁∗︁ and MP2/6‐311++G∗︁∗︁ levels. And only one configuration was obtained for each lithium bond system. All the equilibrium geometries were confirmed to be stable state by analytical frequency computations. The calculations showed that all the N(2)–Li(4) bond lengths increased obviously and the red shift of N(2)–Li(4) stretching frequency occurred after complexes formed. The calculated binding energies with BSSE and zero‐point vibrational energy corrections of complexes I, II and III are −26.04, −24.86 and −30.02 kJ·mol−1 via an MP2 method, respectively. Natural bond orbital (NBO) theory analysis revealed that the three complexes were all formed with π type lithium bond interaction between ethylene, acetylene, or benzene and amido‐lithium.