Design, Synthesis, and Application of Enantioselective Coupling Reagent with a Traceless Chiral Auxiliary
摘要:
Stable chiral N-triazinylbrucinium tetrafluoroborate enantioselectively activates racemic carboxylic acids yielding enantiomerically enriched amides, esters, and dipeptides with er from 8:92 to 0.5:99.5. Due to the departure of a chiral auxiliary after the activation of the carboxylic function, all of the subsequent stages of the coupling reaction proceed without any perturbation caused by a chirality discriminator (traceless). Therefore, the advantageous coupling conditions, configuration, and enantiomeric purity of the final product are entirely predictable from the model experiment.
The design, synthesis, and application of a chiral coupling reagent derived from strychnine for the enantioselective activation of a carboxylic group
作者:Beata Kolesińska、Katarzyna Kasperowicz、Marek Sochacki、Adam Mazur、Stefan Jankowski、Zbigniew J. Kamiński
DOI:10.1016/j.tetlet.2009.06.105
日期:2010.1
The concept of a chiralcouplingreagent for the enantioselectivesynthesis of peptides with a predictable configuration and enantiomeric purity from racemic substrates is presented. The reagent was prepared by treatment of strychninium tetrafluoroborate with 2-chloro-4,6-dimethoxy-1,3,5-triazine in the presence of sodium bicarbonate yielding N-(4,6-dimethoxy-1,3,5-triazin-2-yl)strychninium tetrafluoroborate