%0 Journal Article
%A Dang, Yanfeng
%A Wang, Zhi-Xiang
%A Wang, Xiaotai
%D 2016
%T Does the Ruthenium Nitrato
Catalyst Work Differently
in Z‑Selective Olefin Metathesis? A DFT Study
%U https://acs.figshare.com/articles/journal_contribution/Does_the_Ruthenium_Nitrato_Catalyst_Work_Differently_in_i_Z_i_Selective_Olefin_Metathesis_A_DFT_Study/2457613
%R 10.1021/om300972h.s001
%2 https://ndownloader.figshare.com/files/4100293
%K metathesi
%K NHC ligand causes
%K 3 cat
%K 3LYP
%K DFT
%K Ruthenium Nitrato Catalyst Work Differently
%K mechanism
%K 3 cat functions
%K chelated ruthenium catalysts
%X In the new class of N-heterocyclic carbene (NHC) chelated
ruthenium
catalysts for Z-selective olefin metathesis, the
nitrato-supported complex 3cat appears distinct from
all the other carboxylato-supported analogues. We have performed DFT
calculations (B3LYP and M06) to elucidate the mechanism of 3cat-catalyzed metathesis homodimerization of 3-phenyl-1-propene. The
six-coordinate 3cat transforms via initial dissociation
and isomerization into a trigonal-bipyramidal intermediate (5), from which two consecutive metathesis reactions via the
side-bound mechanism lead to (Z)-PhCH2CHCHCH2Ph (major) and (E)-PhCH2CHCHCH2Ph (minor). In the overall mechanism, 3cat functions similarly to the pivalate-supported analogue 1cat. The substitution of a smaller nitrato group does not
change the side-bound olefin attack mechanism for either the initiation
or homocoupling metathesis. The chelation of the NHC ligand causes
this class of Ru catalysts to favor the side-bound over the bottom-bound
mechanism. The calculated energetics corroborate the experimental
observation that 3cat is somewhat more active than 1cat in catalyzing the homodimerization of 3-phenyl-1-propene.
%I ACS Publications