ISSN:
1573-1111
Schlagwort(e):
Crown ether
;
hydrazine
;
X-ray crystal structure
;
methanol
;
cation binding
;
transition metals
;
post-transition metals
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract Hydrazino-crown ethers have been synthesized in only 3 or 4 steps starting from 1,2-diacetylhydrazine. The X-ray crystal structure of protonated hydrazino-19-crown-7 (2) showed that one of the hydrazino nitrogen atoms was directed outside the ring cavity. A solvent methanol molecule is held in the cavity of the host ligand by three hydrogen bonds involving two hydrogen atoms bonded to nitrogens of the ligand and the alcohol hydrogen of the methanol. The logK values for the interaction of2 with CH3NH + 3 , Ag+, Pb2+, and Cd2+ were much less than those for the interaction of symmetrical triaza-l8-crown-6 (5) with the same cations. Hydrazino-crown2 reduced silver ions to silver metal when a solution of2 and silver ions in DMSO was allowed to stand for several days.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01041886
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