Conformational Changes of an N,N'-Dimethyl-Substituted Dithionoamido-18- Crown-16 Macrocycle
Abstract
Dithionoamide ligand 8 exhibited a time-dependent optical rotation. The first measurement was taken after two minutes of dissolution of the crystals (recrystallized from ethanol). The optical rotation of this solution increased gradually and after 30 min. it was + 106.0 degrees, after 40 min. + 110.4 degrees, after 60 min. + 112.2 degrees and after 90 min. + 112.3 degrees. The optical rotation of the solution was then checked daily for 2 weeks, but no additional changes were observed. When 8 was recovered from the chloroform solution and recrystallized from ethanol, the resulting crystalline 8 had the same optical rotation and mp as the original solid. As early as 2 min. after dissolving the crystals, new peaks appeared which can be attributed to a second, less symmetrical conformer. After 40 min (about the time equilibrium was established) the H NMR spectrum indicated the presence of a third conformer as well.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 15, 1992
- Accession Number
- ADA248099
Entities
People
- J. C. Curtis
- J. S. Bradshaw
- N. K. Dalley
- P. Huszthy
- Reed Izatt
Organizations
- Brigham Young University