ISSN:
1434-193X
Keywords:
4,4′-Bipyridine
;
NMR spectroscopy
;
Pyridinophanes
;
X-ray crystal structure determination
;
Macrocycles
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Syntheses of nine novel phanes derived from 4,4′-bipyridine incorporating new spacer elements are described together with their structural and spectroscopic properties. Starting from the previously unknown pyridine-bridged bis(4,4′-bipyridinium) dication 2 and various bis(bromomethyl)arenes, macrocycles 3-7 were prepared in a simple heterogeneous liquid-liquid reaction in satisfactory yields. In complementary experiments starting from bis(4,4′-bipyridinium) compounds 12-14 with substituted xylenes as spacers, ring closure was performed with 2,6-bis(bromomethyl)pyridine (1) to furnish compounds 16-18 in low yield. Temperature-dependent NMR-spectroscopic studies of the macrocycles were performed to investigate their conformational behaviour. The X-ray crystal structures for phanes 3,4 and 6 illustrate the preferred anti conformation of the macrocycles in the solid state. Consecutive reactions at the pyridine bridge were not successful; however, anisolophane 7 was converted into nitroanisolophane 11 by simple nitration of the anisolo spacer in excellent yield.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
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