N-aryl pyrazoles: DFT calculations of CH acidity and deprotonative metallation using a combination of lithium and zinc amides
作者:Floris Chevallier、Yury S. Halauko、Christelle Pecceu、Ibrahim F. Nassar、To Uyen Dam、Thierry Roisnel、Vadim E. Matulis、Oleg A. Ivashkevich、Florence Mongin
DOI:10.1039/c1ob05267e
日期:——
A series of N-aryl and N-heteroaryl pyrazoles have been deproto-metallated using a 2,2,6,6-tetramethylpiperidino-based mixed lithium–zinc combination. Mono-, di-, and tri-iodides have been obtained after subsequent trapping with iodine, depending on the substrate and on the quantity of base used. The results have been discussed in the light of the CH acidities of the substrates, determined both in the gas phase and in THF solution using the DFT B3LYP method.
一系列N-芳基和N-杂芳基吡唑化合物通过基于2,2,6,6-四甲基哌啶的混合锂-锌试剂进行了去质子金属化反应。在随后与碘的捕获反应中,根据底物和所用碱的量的不同,分别得到了单碘、二碘和三碘化合物。研究结果根据底物的CH酸性进行了讨论,这些酸性在气相和THF溶液中均通过DFT B3LYP方法进行了测定。