Oxirene retro Diels-Alder reactions

Fig. 3.5 Attempted retro Diels-Alder reactions on formal adducts of an oxirene or benzooxirene with benzene. The adducts prefer to isomerize rather than extrude an oxirene...

Fig. 3.13 The retro Diels-Alder reaction generating oxirene (and benzene) was compared with analogous reactions for cyclopropene and ethene, and with the prototype retro Diels-Alder reaction [72]. The level is MP2(fc)/6-31G(df, p). Bond lengths (A) are shown, and in parentheses Lowdin bond orders for HF/3-21G calculations on the MP2(fc)/6-31G(df p) geometries...

Delamere, C., Jakins, C., and Lewars, E., On the generation of oxirene and dimethyloxirene by retro-Diels-Alder reactions and reactions of dimethyloxirene a computational study. Can. J. Chem., 80, 94, 2002. 

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