Design, synthesis, and application of enantioselective coupling reagent with a traceless chiral auxiliary.
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.
Kolesinska
Beata
B
Institute of Organic Chemistry, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland.
Kaminski
Zbigniew J
ZJ