ISSN:
0170-2041
Keywords:
Macrocycles
;
Template synthesis
;
Conformers
;
Sulfonamides
;
Pyridines
;
Phenanthrolines
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Bimacrocyclic concave pyridinebissulfonamides 2 and concave 1,10-phenanthrolinebissulfonamides 4 have been synthesized by bridging macrocyclic pyridinediamines 12 or 1,10-phenanthrolinediamines 16 with alkylenebis(sulfonyl chloride)s 14. In contrast to concave pyridine- and 1,10-phenanthrolinebislactams 1 and 3, the new compounds 2 and 4 exhibit simpler 1H-NMR spectra and sharper melting points due to the absence of amide conformers; in comparison to 1, the basicities of 2 are decreased by a factor of ca. 100. By introduction of donor substituents into the 4-position of the pyridine ring the basicity loss can be easily compensated. The 4-diethylamino substituent increases the basicity of the concave pyridines 1 and 2 as expected (ca. + 4 pK units). Since no deviations from the expected basicity and reactivity for the amino-substituted concave pyridines 1 and 2 have been found, also in these sterically hindered pyridines, the pyridine nitrogen atom is the centre of basicity and reactivity. - The synthesis of new building blocks is described, i.e. 4-diethylamino-2,6-pyridinedicarbaldehyde (9c), the polyether-based bis(sulfonyl chloride) 14b, the monomacrocyclic diamines 12e-h with a pentaethyleneglycol chain or a 4-diethylamino substituent.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1991199101172
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