Aliphatic Polyketones as Shapable Molecular Chains

Abstract

Aliphatic polyketones are structurally flexible compounds that can induce and fix various conformations using ketone-related molecular interactions and reactions, such as hydrogen-bonding interactions and nucleophilic additions, respectively. These characteristics are advantageous to create structurally diverse molecules. However, difficulty in synthesis and reaction control of aliphatic polyketones depends on the ketone sequence. Recently, a new ketone sequence comprising alternating 1,3- and 1,4-diketone subunits was developed using stepwise oligomerization of an acetylacetone derivative. This sequence allowed preparation of the polyketone chains as their discrete forms with fixed chain length. Thus, various compounds including chromophores and coordination assemblies were generated through chemo-, regio-, and stereoselective transformations. This account focuses on the recent developments in molecular synthesis using aliphatic polyketone chains bearing an alternating 1,3- and 1,4-diketone sequence.