A computational study of the interplay of steric and electronic effects in the stabilization of 1,3-(diamino)oxyallyls

Air‐Stable Oxyallyl Patterns and a Switchable N‐Heterocyclic Carbene

“…[38,39] Thestructure of the oxyallyl pattern remains remarkably unchanged within compounds 4 + , 6, 7,and 8.Importantly,the lengths of the N2ÀC2 (134-137 pm), C2ÀC3 (142-145 pm), and C3ÀO1 (126-129 pm) bonds correspond to those previously predicted for diaminooxyallyl species (about 138, 144, and 128 pm, respectively). [17] Thef rontier molecular orbitals (MOs) also remain very similar within the series and correspond to the HOMO (highest occupied MO) and LUMO (lowest unoccupied MO) of a1 ,3-diaminooxyallyl fragment, with as econd-order contribution from the rest of the heterocycle (see the Supporting Information). This is especially striking in the case of 6 ( Figure 3).…”

“…They are persistent enough in solution for NMR characterization . Importantly, as the parent oxyallyl pattern experiences significant electronic perturbation, the diaminocyclopropanone forms have become irrelevant high‐energy isomers . Thus, the stabilized oxyallyl species C could be considered novel electron‐rich organic functionalities with reactivity of their own.…”

“…[15,16] Importantly,a st he parent oxyallyl pattern experiences significant electronic perturbation, the diaminocyclopropanone forms have become irrelevant high-energy isomers. [17] Thus,t he stabilized oxyallyl species C could be considered novel electron-rich organic functionalities with reactivity of their own. They undergo thermal rearrangement through N!Oa ryl migration of substituents, [15,18] as well as one-electron oxidation at low potentials to yield highly air-persistent radical cations CC + .…”