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Summary: Water-processable conducting polyaniline derivatives (PANIs), such as polyaniline (PANI), poly(o-methylaniline) and poly(o-methoxyaniline), were synthesized by in situ chemical polymerization of the corresponding achiral monomer in the presence of the novel chiral polymeric template, chondroitin sulfate. The resulting conducting PANIs were doped and complexed with chondroitin sulfate (CHS) to form intertwined intermacromolecular complexes of PANIs-CHS, which was confirmed by UV-vis and FTIR spectroscopy. The induction of the excess one-handed helical structure into PANIs was confirmed by circular dichroism (CD) spectroscopy with the characteristic bisignate bands at approximately 400 and 450 nm for the emeraldine salt. The effect of ionic strength was investigated on the formation of the intertwined PANI-CHS complex and the induction of chirality into PANI by adding NaCl to the reaction solution. The CD spectral change of PANI‐CHS in the cycle of dedoping and redoping was also studied, and it was found that intermacromolecular complexation helps to stabilize the chiral conformation in PANI against racemization. Interestingly enough, it was found that optically active PANI‐CHS exhibited pH‐sensitive chiroptical properties. A study of the conductivity, electrochemical activity and the chiroptical properties in different redox states of PANIs provided proof for their use as chiral electrode and electroactively chiral material.Structure of the complexes of PANIs-CHS.

Two routes have been developed inorder to prepare an inclusion complex of polyaniline (PANI) and β‐cyclodextrin (βCyD). The first route was to in situpolymerize N‐phenyl‐1,4‐phenylenediamine (PPD) which was encapsulated in βCyD in advance. The formation of an inclusion complex was confirmed by UV‐vis, circular dichroism (CD), and NMR spectra. It was found that the synthesized complex was readily dissolved in a range of solvents due to the solubility of βCyD. In these solvents, PANI was well encapsulated by βCyD with some conformation change in the chain of PANI, which was proved by the CD spectra of PANI. The second route involved preparing the inclusion complex by post‐encapsulation of PANI emeraldine base (EB) into βCyD in aqueous solution at room temperature. The encapsulation of EB into βCyD was confirmed by FT‐IR and UV‐vis spectra. The band shift in UV‐vis spectra indicated that the inclusion complexation was a gradual process, and the change in the chain conformation of PANI was also observed after it was encapsulated into βCyD. Copyright © 2003 John Wiley & Sons, Ltd.

Two routes have been developed inorder to prepare an inclusion complex of polyaniline (PANI) and β-cyclodextrin (βCyD). The first route was to in situ polymerize N-phenyl-1,4-phenylenediamine (PPD) which was encapsulated in βCyD in advance. The formation of an inclusion complex was confirmed by UV-vis, circular dichroism (CD), and NMR spectra. It was found that the synthesized complex was readily dissolved in a range of solvents due to the solubility of βCyD. In these solvents, PANI was well encapsulated by βCyD with some conformation change in the chain of PANI, which was proved by the CD spectra of PANI. The second route involved preparing the inclusion complex by post-encapsulation of PANI emeraldine base (EB) into βCyD in aqueous solution at room temperature. The encapsulation of EB into βCyD was confirmed by FT-IR and UV-vis spectra. The band shift in UV-vis spectra indicated that the inclusion complexation was a gradual process, and the change in the chain conformation of PANI was also observed after it was encapsulated into βCyD. Copyright © 2003 John Wiley & Sons, Ltd.

A wool–Pt complex was prepared by the reaction of wool with chloroplatinic acid in ethanol solution, and was found to be useful as a chiral catalyst for the asymmetric hydrogenation of some ketones to corresponding chiral alcohols, such as 3‐methyl‐2‐butanone to (R)‐3‐methyl‐2‐butanol, 4‐methyl‐2‐pentanone to (R)‐4‐methyl‐2‐pentanol, acetophenone to (R)‐1‐phenylethanol and propiophenone to (R)‐1‐phenyl‐1‐propanol at 30 °C and under an atmospheric hydrogen pressure.

A wool–Pt complex was prepared by the reaction of wool with chloroplatinic acid in ethanol solution, and was found to be useful as a chiral catalyst for the asymmetric hydrogenation of some ketones to corresponding chiral alcohols, such as 3-methyl-2-butanone to (R)-3-methyl-2-butanol, 4-methyl-2-pentanone to (R)-4-methyl-2-pentanol, acetophenone to (R)-1-phenylethanol and propiophenone to (R)-1-phenyl-1-propanol at 30 °C and under an atmospheric hydrogen pressure. In the case of hydrogenation of 3-methyl-2-butanone to (R)-3-methyl-2-butanol, when a proper content of Pt in the wool–Pt complex was selected, the yield and optical yield amounted to about 100% respectively, and the wool–Pt complex catalyst could be reused without any change in the optical catalytic activity. Wool is a very cheap natural bio-polymer ligand, and Wool–Pt complex is very easy to prepare, and it is a very active, enantioselective and stable chiral catalyst for asymmetric hydrogenation of some ketones. Copyright © 1999 John Wiley & Sons, Ltd.

One preferred handed helical structure was induced into the polyaniline main chains by chemical polymerization of achiral aniline in the presence of dextran sulfate as a molecular template, and this affords a novel chemical route for synthesis of chiral conducting polymers.