through transition structure TS16-17 to provide adduct 17 which is stabilized by a hydrogen bonding interaction between in-situ-generated triflic acid and the phenolate ligand. This step is calculated to occur with an activation barrier of around 11 kcal/mol and is endergonic by about 8 kcal/mol. Following this, the resulting triflic acid protonates the bipyridine nitrogen trans to the oxo ligand (N b ) in a thermodynamically favorable process to give intermediate 19. Due to the π conjugation within the bipyridine ligand, the addition of the proton to N b significantly reduces the basicity of N a and, thus, it binds less strongly to the iodine(V) center in 19. This is consistent with the longer I-N a distance in 19 (2.426 Å) than in 18 (2.356 Å) (Figure ). In other words, N b protonation reduces the coordinative stability of the iodine(V) molecule and it changes from a rather inert to a more labile complex. The dissociation of 9 from 19 produces 20 in a thermoneutral fashion which then isomerizes to more stable structure 21_OTf. Since the phenolate provides a weaker trans influence relative to the phenyl, the triflate binds more strongly to the iodine atom in 21_OTf, resulting in this complex being more stable than 20.