Mesomeric Betaines Based on Adamantylated 1,2,4‐Triazolo[4,3‐
<i>a</i>
]pyrimidin‐5‐ones: Synthesis, Structure and Conversion into Anionic N‐Heterocyclic Carbenes
作者:Ekaterina S. Sheina、Tatyana S. Shestakova、Sergey L. Deev、Igor A. Khalymbadzha、Pavel A. Slepukhin、Oleg S. Eltsov、Alexander S. Novikov、Vadim A. Shevyrin、Valery N. Charushin、Oleg N. Chupakhin
DOI:10.1002/asia.202201306
日期:2023.3
The C−N coupling of 1,2,4-triazolo[1,5-a]pyrimidin-7-ones with 1-adamantanol/1-bromoadamantane leads to 1,2,4-triazolo[4,3-a]pyrimidinium-5-olates, which are considered as mesomeric betaines (MBs). Deprotonation of these MBs with lithium bis(trimethylsilyl)amide led to new types of anionic N-heterocyclic carbenes (aNHCs), which were characterized by 1D 13C NMR spectroscopy and trapping reactions with
1,2,4-三唑并 [1,5- a ]pyrimidin-7-ones 与 1-金刚烷醇/1-溴金刚烷的 C−N 偶联生成 1,2,4-三唑并[4,3- a ]嘧啶鎓-5-olates,被认为是内消旋甜菜碱 (MB)。用双(三甲基甲硅烷基)氨基锂对这些 MB 进行去质子化,生成新型阴离子 N-杂环卡宾 (aNHC),其特征在于 1D 13 C NMR 光谱和与硫和异硫氰酸苯酯的捕获反应。