Breaking the <i>tert</i>-Butyllithium Contact Ion Pair: A Gateway to Alternate Selectivity in Lithiation Reactions
作者:Michael P. Crockett、Jeanette Piña、Achyut Ranjan Gogoi、Remy F. Lalisse、Andrew V. Nguyen、Osvaldo Gutierrez、Andy A. Thomas
DOI:10.1021/jacs.2c13047
日期:2023.5.17
by NMR and DFT methods. It was determined that hexamethylphosphoramide (HMPA) can shift the equilibrium of t-BuLi to include the triple ionpair (t-Bu–Li–t-Bu)−/HMPA4Li+ which serves as a reservoir for the highly reactive separated ionpair t-Bu–/HMPA4Li+. Because the Li-atom’s valences are saturated in this ionpair, the Lewis acidity is significantly decreased; in turn, the basicity is maximized
通过NMR和DFT方法详细研究了路易斯碱性磷酰胺对叔丁基锂聚集结构的影响。据确定,六甲基磷酰胺 (HMPA) 可以改变t- BuLi 的平衡,以包含三重离子对 ( t -Bu–Li– t -Bu) - /HMPA 4 Li + ,它充当高反应性分离离子的储存库对t -Bu – /HMPA 4 Li + 。由于该离子对中锂原子的价态已饱和,路易斯酸度显着降低;反过来,碱度被最大化,这使得氧杂环内的典型定向效应被覆盖,并且远程 sp 3 C-H 键被去质子化。此外,利用这些新获得的锂聚集态开发了一种简单的γ-锂化和苯并二氢吡喃杂环与各种烷基卤化物亲电子试剂的捕获方案,收率良好。
[EN] 4-HYDROXYBUTYRIC ACID ANALOGS<br/>[FR] ANALOGUES DE L'ACIDE 4-HYDROXYBUTYRIQUE
申请人:CONCERT PHARMACEUTICALS INC
公开号:WO2010124046A1
公开(公告)日:2010-10-28
This invention relates to novel derivatives of 4-hydroxybutyric acid and prodrugs thereof, and pharmaceutically acceptable salts of the foregoing. This invention also provides pharmaceutical compositions comprising a compound of this invention and the use of such compositions in methods of treating narcolepsy, fibromyalgia, other disorders or conditions that are beneficially treated by improving nocturnal sleep or by administering sodium oxybate.