Accession Number : ADA309259

Title :   Chiral Pyridine-Based Macrobicyclic Clefts: Enantiomeric Recognition of Chiral Organic Ammonium Salts.

Descriptive Note : Technical rept.,

Corporate Author : BRIGHAM YOUNG UNIV PROVO UT DEPT OF CHEMISTRY

Personal Author(s) : Heller, Paul C. ; Bradshaw, Jerald S. ; Young, J. J. ; Zhang, Xian X. ; Izatt, Reed M.

PDF Url : ADA309259

Report Date : MAY 1996

Pagination or Media Count : 12

Abstract : Achiral macrobicyclic cleft containing a pyridine ring (1) formed a complex at 25 deg C in 50% CH3OH/50% CHCl3(v/v), with a primary ammonium salt (log K= 3.15) as evidenced by a significant change in the (1)H NMR spectrum. Highly organized pyridine-containing macrobicycle (S,S,S,S)-2 exhibited recognition at 25 deg C in 20% C2H5OH/80% 1,2-C2H4Cl2 (v/v) for the (S) enantiomer of alpha- (1-naphthyl)ethylammonium perchlorate (NapEt) over its (R) form (delta log K= 0.85). This high recognition factor probably reflects an increase in molecular rigidity by the introduction of a second macroring on the monocyclic pyridinocrown ligand.

Descriptors :   *ORGANIC COMPOUNDS, *AMMONIUM COMPOUNDS, *SALTS, *PYRIDINES, MOLECULES, LIGANDS, RECOGNITION, RINGS, RIGIDITY, ETHYL RADICALS, PERCHLORATES.

Subject Categories : Organic Chemistry
      Inorganic Chemistry
      Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE