Gibbs energy profile for (A) the concerted 1,3-dipolar cycloaddition of 1 awith 11 and (B) the analogous stepwise reaction of 1 awith 3 b′. For efficient computations at the SMD(THF)/ωB97X−D/def2-TZVP//SMD(THF)/B3LYP−D3BJ/def2-SVP level of theory, the ethyl groups of 3 bwere replaced by methyl groups in 3 b′. All energy values correspond to Boltzmann-weighted averages for ensembles of conformers. For each reaction, only the energetically more favorable diastereomers (ProdAor ProdB) for each regioisomeric product (1,2- or 1,4-product, see the Figure for the definition of these numbers) are depicted. For the full energy profiles and details on the computations, see Figures S111 and S113 in the SI.
