Practical Routes to 2,6-Disubstituted Pyridine Derivatives.
L. Vandromme, H.-U. Reissig, S. Gröper, J. P. Rabe – 2008
We report the synthesis of a series of 2,6-disubstitutedpyridines in a straightforward manner starting from readily available 2-substituted pyridines. The main sequence involves a selective α-lithiation reaction with halogen functionalization followed by a Grignard reaction catalyzed by Fe(acac)3. After demonstration of the easy feasibility of this strategy by synthesizing 2,6-disubstituted pyridines 1, the route was applied to obtain pyridine derivatives bearing electron-donating or electron-withdrawing groups. Thus, a series of pyridines bearing an aryl moiety in the 6-position and an alkyl chain in the 2-position was obtained. The pyridines were studied for their self-assembly abilities at the interface between an organic solution and the basal plane of graphite. Preliminary STM results for one compound are reported.