NMR Spectroscopic Characterization of Charge Assisted Strong Hydrogen Bonds in Bronsted Acid Catalysis.

ABSTRACT: Hydrogen bonding plays a crucial role in Brønsted acid catalysis. However, the hydrogen bond properties responsible for the activation of the substrate are still under debate. Here, we report an in depth study of the properties and geometries of the hydrogen bonds in (R)-TRIP imine complexes (TRIP: 3,3'-Bis(2,4,6-triisopropylphenyl)-1,1'-binaphthyl-2,2'-diylhydrogen phosphate). From NMR spectroscopic investigations ¹H and ¹⁵N chemical shifts, a Steiner-Limbach correlation, a deuterium isotope effect as well as quantitative values of ¹J_NH,^2hJ_PH and ^3hJ_PN were used to determine atomic distances (r_OH, r_NH, r_NO) and geometry information. Calculations at SCS-MP2/CBS//TPSS-D3/

SUBMITTER: Sorgenfrei N 

PROVIDER: S-EPMC5266430 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature