Rearrangements and Stereomutations of Metallacycles Derived from Allenes and Imidozirconium Complexes Forrest E. Michael Andrew P. Duncan Zachary K. Sweeney Robert G. Bergman 10.1021/ja045607k.s004 https://acs.figshare.com/articles/dataset/Rearrangements_and_Stereomutations_of_Metallacycles_Derived_from_Allenes_and_Imidozirconium_Complexes/3301021 The mechanisms of the rearrangements and stereoinversion of azametallacyclobutenes generated via [2+2] cycloaddition of allenes and imidozirconium complexes have been studied. Metallacycles derived from allenes bearing β-hydrogen atoms racemize at room temperature by reversible β-hydride elimination, a process which is also responsible for their eventual conversion to monoazadiene complexes. Metallacycles derived from diarylallenes racemize by reversible thermal bond homolysis at 95 °C; racemization of these metallacycles is also catalyzed by mild oxidants. 2005-02-16 00:00:00 bond homolysis Imidozirconium Complexes Metallacycles Derived monoazadiene complexes room temperature diarylallenes racemize imidozirconium complexes