A range of optically active pyrrole monomers have been synthesized in which a
chiral sub- stituent is covalently bonded either to the pyrrole N or C3 ring
position, namely
(–)-(1R)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide,
(+)-(1S)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide,
(–)-(1R)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide,
(+)-(1S)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide,
(+)-(2S)-2-(1H-pyrrol-1-yl)propionic
acid,
(+)-(1S)-N-(1-phenyl-ethyl)pyrrole,
and
(–)-(1R)-N-(1-phenylethyl)pyrrole.
Their chiroptical properties have been established by circular dichroism
spectroscopy. Electropolymerization of the three
N-substituted pyrrole monomers provided films of chiral
conducting polymers, whose electrical and spectroscopic properties are
described. Although oxidation of the C3 substituted pyrrole monomers was also
facile, electrodeposition was poor and films of the associated polymers could
not be obtained.