ISSN:
0941-1216
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A new synthesis of the title crown via isoxazolo crown ether 7 and macrocyclic bis-β-eneaminoketone 10 is described. 7 can be synthesized in 14% yield by a non-template double-[3+2] cycloaddition of dinitrileoxide 5 prepared in situ from dinitropolyether 19 by dehydration with Ph-NCO and alkyne 6. The compounds 16, 17 and 18 are synthesized by the same synthetic strategy. Comparable IR and 1H NMR spectroscopic data of macrocyclic and non-cyclic compounds show, that macrocyclic conformation stabilizing effects can be ruled out. The structures of the macrocycles 1, 7, 10 and that of the Hg(II)-complex 25, synthesized by reaction of 1 with Hg(OAc)2 were established by single-crystal X-ray structure analyses. Both inter- and intramolecular hydrogen bonds are observed for the macrocyclic bis-β-eneaminoketone 10, whereas only intramolecular hydrogen bonds are formed by 1.In the Hg(II)-complex of 1 the mercury is bonded to two methylene groups. C—Hg—C is almost linear [177(1)°], the mean Hg—C distance amounts to 215(1) pm. In addition to the Hg—C bonds, each Hg makes a short contact to a carbonyl oxygen in a neighbouring molecule in the plane perpendicular to the C—Hg—C axis [Hg(1)—O(1) = 279(1) pm, Hg(2)—O(5) = 284(1) pm].
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prac.19983400207
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