Current time in Korea 10:32 Feb 26 (Wed) Year 2020 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 9, Number 6
June 20, 1988 

The Pfeiffer Effect of [CoⅡ(acac)2(diamine)] with Cinchona Alkaloid in Some Organic Solvents
Chang Eon Oh*, Yang Kim
The Pfeiffer effect was examined on the systems of racemic [CoⅡ(acac)2(diamine)] with d-cinchonine and l-cinchonidine as chiral environment substances in methanol, ethanol, chloroform and methanol-chloroform mixture solvents. It was found that the Δ-enantiomer is enriched for the [CoⅡ (acac)2(diamine)]-d-cinchonine system, but the Λ -enantiomer is enriched for the [CoⅡ (acac)2(diamine)]-l-cinchonidine system. The complexes having no N-H protons such as [CoⅡ (acac)2(bpy)] and [CoⅡ(acac)2(phen)] were Pfeiffer-inactive in alcoholic solvents, where bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline. This was interpreted to mean that the hydrogen bonding between N-H proton of diamine ligand and C-9 hydroxyl group of alkalid plays an important role in the chiral discrimination. And the rate of antiracemization (kanti) by the Pfeiffer effect was also measured for the [CoⅡ (acac)2(diamine)]-d-cinchonine system in alcoholic solvents. It was found that the rate of appearance of the Pfeiffer effect was enhanced as the concentration of added chloroform is increased.
355 - 359
Full Text