title: Computational study on the pKa shifts in proline induced by hydrogen-bond-donating cocatalysts.
abstract: The pKa shifts of proline induced by a family of hydrogen-bond-donating cocatalysts were computationally evaluated with the M06-2x/6-311++G(2df, 2p)//B3LYP/6-31+G(d)(SMD) method. The calculation predicted that the acidity of proline could be increased by more than 9 pKa units in nonpolar solvents (n-hexane and toluene) when it assembles with hydrogen-bond-donating cocatalysts, which would contribute to the dramatically enhanced catalytic properties. For hydrogen-bond-donating cocatalysts, their relative abilities to induce the pKa shifts of proline in the gas phase and common organic solvents were established and were found to be well-correlated with their acidities. The results may aid in future development of modularly designed supramolecular catalysis--the assembly of catalyst species by harnessing multiple weak intermolecular interactions.
authors.affiliation: State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, Department of Chemistry, Nankai University , Tianjin 300071, China.
authors.forename: Xiao-Song
authors.initials: XS
authors.lastname: Xue
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Jin-Pei
authors.initials: JP
authors.lastname: Cheng
mesh_terms: D002384:Catalysis; D006860:Hydrogen Bonding; D015394:Molecular Structure; D011392:Proline / Q000031:analogs & derivatives* / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D011392:Proline