om7b00287_si_001.pdf (1.04 MB)
Toward Factors Affecting the Degree of Zinc Alkyls Oxygenation: A Case of Organozinc Guanidinate Complexes
journal contribution
posted on 2017-06-19, 18:22 authored by Michał
K. Leszczyński, Iwona Justyniak, Janusz LewińskiWhile extensive research has been
carried out on the oxygenation
of alkylzinc complexes for decades, this issue still remains unresolved
and significant uncertainties concerning the mechanism of these reactions
and the composition of the resulting products persist. These reactions
are believed to proceed via the initial formation of ROOZn(L) species,
but studies on the oxygenation reactions have been substantially impeded
by the low stability of the alkylperoxides. This report describes
the oxygenation of a tert-butylzinc guanidinate,
i.e. a tBuZn(L)-type complex (L = deprotonated 1,4,6-triazabicyclo[3.3.0]oct-4-ene),
and the isolation and characterization of an unprecedented aggregate
based on a combination of a ROOZn(L) moiety and two parent tBuZn(L) molecules, {[tBuZn(L)]2[tBuOOZn(L)]}. Further study revealed that examined tert-butylzinc guanidinate molecules exhibit an ability
to entrap other oxygenated species, which was demonstrated by an aggregate
containing a tert-butylzinc tert-butylperoxide and two tBuZn(L) molecules, {[tBuZn(L)]2[tBuOZntBu]}. Thus, the reported studies indicate that entrapment of the
product of an oxygenation reaction by the parrent alkylzinc species
is another important factor controlling the oxygenation of organometallics.