Nagasaki, Takeshi published the artcileSynthesis and solvent extraction studies of novel calixarene-based uranophiles bearing hydroxamic groups, SDS of cas: 1798-04-5, the publication is Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) (1991), 1063-6, database is CAplus.
Calix[n]arene-based uranophiles [I; n = 4 (II), 6 (III)] bearing hydroxamic groups on the lower rim have been synthesized and the extractability (Ex%) and the selectivity towards uranyl ion (UO22+) estimated in a two-phase (water-chloroform) solvent extraction system. Ex% for II and III increases from pH 2 and saturation is reached at around pH 5 where 100% extractability occurs. Since the pKa values for hydroxamic acids are 8-9, the apparent pKa shift caused by the UO22+-complexation amounts to 6-7 pK units. Extraction of UO22+ from aqueous carbonate solution established that III in the organic phase can compete efficiently with CO32- ions in the aqueous phase for UO22+ whereas in II and a calix[6]arene-based uranophile bearing six carboxy groups, UO22+ is reextracted to the aqueous phase. The difference indicates that III which has the hexacoordination geometry preorganized for the binding of UO22+, is superior to II as a uranophile. The selectivity of III is superior to the uranophile bearing six carboxy groups. The Ex% values for III are scarcely affected by the addition of competing metal cations (except Fe3+). These results shows that III serves as an excellent UO22+-selective extraction reagent.
Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) published new progress about 1798-04-5. 1798-04-5 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2-(4-(tert-Butyl)phenoxy)acetic acid, and the molecular formula is C12H16O3, SDS of cas: 1798-04-5.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia