No abstract

A unique chemical transformation, the base-induced aerobic dimerization of ethyl 4-(2,5-dimethylthiophen-3-yl)-3-ketobutanoate leading to photochromic diarylethene with a 4-hydroxy-4-methylcyclopent-2-ene-1-one as an ethene bridge, is described. This compound is easily subjected to various chemical modifications and can be used as a new diarylethene precursor to produce photoactive compounds with desired properties and functions.

The Nazarov reaction of divinylketones of type (I) affording cyclopentenone derivatives of type (II) is the key step in the synthesis of new photochromic diarylethenes. -(SHIRINIAN*, V. Z.; LVOV, A. G.; YANINA, A. M.; KACHALA, V. V.; KRAYUSHKIN, M.; Chem. Heterocycl. Compd. (N. Y., NY, U. S.) 51 (2015) 3, 234-241, http://dx.