| Resumo: | N,N-Boc2 amides have emerged as the most common class of acyclic twisted amides that have been engaged in a range of C–N activation and cross-coupling processes of ubiquitous amide bonds. These amides are readily synthesized from primary amides through a site-selective tert-butoxycarbonylation. Due to the steric bulk of di-tert-butoxy groups, these amides exhibit significant C N bond twisting, which promotes N–C bond cleavage, facilitating their use in cross-coupling reactions. Herein, we present a computational blueprint for the C N bond rotation in N,N-Boc2 amides, revealing that the rotational barrier and twist angle (τ) are influenced by the nature of the substituents at the sp2 carbon position. Sterically hindered substituents exhibit the highest distortions, leading to lower rotation barriers. Rotation along the C N bond is accompanied by phenyl ring rotation to minimize steric clashes. A strong correlation between the rotational barriers and the HOMO energies is observed. These findings provide key insights into the fundamental role of amide bond distortion in C–N activation processes
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