Ulatowski F, Jurczak J. Chiral recognition of carboxylates by a static library of thiourea receptors with amino acid arms.
J Org Chem 2015;
80:4235-43. [PMID:
25867541 DOI:
10.1021/acs.joc.5b00403]
[Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Chiral recognition is based on a large network of very subtle interactions whose outcome is difficult to predict. A combinatorial approach is therefore the most suitable to search for the most efficient receptor and obtain a structure-enantioselectivity correlation. We synthesized a set of 12 receptors constructed with 1,9-diaminoantracene and α-amino acid esters, linked via thiourea groups. The association constants and enantioselectivities for the complexes with mandelate and N-acetylphenylalanine were determined by competitive NMR titrations. Association constants quite regularly depend on the substituents in the receptor structure, but the distribution of enantioselectivities across the library could not easily be rationalized.
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