Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA.
J Am Chem Soc. 2012 Sep 12;134(36):14764-71. doi: 10.1021/ja306276w. Epub 2012 Aug 27.
In diethyl ether, N-Boc-2-lithio-2-arylpiperidines have been found to be configurationally stable at -80 °C, whereas N-Boc-2-lithio-2-arylpyrrolidines are configurationally stable at -60 °C. Several tertiary benzylic carbanions derived from enantioenriched 2-aryl heterocycles have been successfully alkylated or acylated with little to no loss of enantiopurity. The scope of the reactions has been explored. The enantiomerization dynamics of N-Boc-2-lithio-2-phenylpyrrolidine and N-Boc-2-lithio-2-phenylpiperidine have been studied in the presence of different solvents and achiral ligands.
在乙醚中,N-Boc-2-锂代-2-芳基哌啶在-80°C 下被发现具有构型稳定性,而 N-Boc-2-锂代-2-芳基吡咯烷在-60°C 下具有构型稳定性。几种衍生自对映体富集的 2-芳基杂环的叔丁基烯丙基碳负离子已成功地进行了烷基化或酰基化,几乎没有对映体纯度的损失。已经探索了反应的范围。在不同的溶剂和手性配体存在下,研究了 N-Boc-2-锂代-2-苯基吡咯烷和 N-Boc-2-锂代-2-苯基哌啶的外消旋化动力学。