Direct synthesis and optical absorbance studies of the first representatives of 3-ylidenemalononitrile derivatives of 2-oxopyrroles containing a phenol moiety

Synthesis of the first 4-oxobutane-1,1,2,2-tetracarbonitriles containing a phenol fragment and their transformation into cyano-substituted pyrrol-2-ones showing three-position molecular switching

“…The presence of a phenolic OH group in the structure of pyrroles 2 and their analogs, as was shown previously, 25,47,48 is promising for the targeted change of optical properties of molecules due to the possibility of phenol/quinoid transformation by the action of bases. The sensitivity of a phenolic hydroxyl group to basic reagents is a routine fact.…”

“…The physical and spectral characteristics of previously described compounds 2a and e corresponded to the literature data. 25…”

“…One of the well-known DOS platforms is tetracyanoethylene adducts with ketones, namely 4-oxoalkane-1,1,2,2-tetracarbonitriles (OTCs) 24–40 (Fig. 1).…”

“…1). Due to the presence of the combination of a carbonyl group and four cyano groups on a four-carbon skeleton, OTCs are highly reactive compounds that can be transformed into furan derivatives, 24 various pyrroles, 25–29 pyridines, 30–32 and pyrans, 33 as well as into fused, 34 bicyclic 35 and spiro 36,37 heterocycles under the action of various reagents. In total, more than twenty directions of OTC transformations have been described in the literature.…”

“…In total, more than twenty directions of OTC transformations have been described in the literature. Moreover, among the products of their transformations, compounds with antitumor activity, 26 molecular switches, 25,27,38 efficient fluorophores 30 (including solid-state ones 31 ), fluorescent sensors 32 and coordination polymers 39,40 have been found.…”