Media type: E-Article Title: Synthesis of cross‐conjugated polyketones by the crossed‐aldol condensation of cyclic ketones with aromatic dialdehydes Contributor: Hudson, Lilith Gentles; Stevens, Malcolm P. imprint: Wiley, 1995 Published in: Journal of Polymer Science Part A: Polymer Chemistry Language: English DOI: 10.1002/pola.1995.080330108 ISSN: 0887-624X; 1099-0518 Keywords: Materials Chemistry ; Organic Chemistry ; Polymers and Plastics Origination: Footnote: Description: <jats:title>Abstract</jats:title><jats:p>Insoluble cross‐conjugated polyketones were prepared from terephthalaldehyde and a variety of cycloaliphatic ketones by the crossed‐aldol condensation. Elemental analyses and infrared spectra suggest that the polymeric aldol intermediates were not completely dehydrated. Evidence is also presented that suggests conjugate addition of the base to the α,β‐unsaturated ketone may occur. Soluble cross‐conjugated polyketones were prepared from terephthalaldehyde and 2‐indanone, which contains no beta hydrogens, and from cycloaliphatic ketones and 1,2‐bis(4‐formylphenoxy)ethane, a dialdehyde containing isolated aldehyde groups. It is proposed, therefore, that the lack of solubility in the terephthalaldehyde‐based polyketones arises from crosslinking via enolate anions formed at the beta position of the cyclic ketones, which are delocalized through the carbonyl groups of neighboring backbone repeating units. © 1995 John Wiley & Sons, Inc.</jats:p>