“…However, there have only been a few reports demonstrating this strategy. − The underdevelopment of this strategy is due to the thermodynamic disfavor, , in which, owing to the strong conjugation effect, the acyl C–O/or C–N bond of the common carboxylic acids and their derivatives is more stable than the acyl C–S bond of thioesters. Indeed, previous studies have employed substrates that have a decreased activation barrier (Scheme a–c), which leads to the use of specially structured substrates (or in situ formed). ,, For example, Plietker’s work limits to the p -chloro-substituted aryl esters .…”