Lack of a "Cesium Effect" on Macrolactonization

Article abstract of DOI:10.1021/jo00009a022

The lactonization of ω-bromoalkanoate ions, run in DMF under preparative conditions and in the presence of counterions, is exploited to show that those synthetic effects whose manifestations has led to the coinage of the term "cesium effect" are simply due to the operation of well-established, rate-decreasing ion-pairing phenomena upon the reactivity of anionic nucleophiles.No peculiarity emerges with cesium when compared with the other alkali-metal ions.