- Peptide-catalyzed kinetic resolution of formamides and thioformamides as an entry to nonracemic amines.
Peptide-catalyzed kinetic resolution of formamides and thioformamides as an entry to nonracemic amines.
Journal of the American Chemical Society (2010-02-18)
Brandon S Fowler, Peter J Mikochik, Scott J Miller
PMID20158213
摘要
We report a fundamentally unique approach to the catalytic kinetic resolution of amine derivatives based on formamide and thioformamide substrates. Readily accessible histidine-containing peptides mediate the kinetic resolutions with as little as 5 mol % catalyst. Selectivity factors (k(rel)) as high as 43.7 were observed under simple reaction conditions utilizing Boc(2)O as the reagent at room temperature. Mechanistic experiments were conducted that established a higher level of reactivity for thioformamide substrates than for their formamide analogues. The products of these asymmetric reactions were shown to be readily converted to desirable building blocks such as N-Boc-amines and the parent chiral formamide compounds.