Synthesis and photochromic properties of novel nonsymmetric dihetarylethenes based on benzindole and thiophene

Novel nonsymmetric dihetarylethenes 3-(5-methoxy-1,2-dimethyl-1H-benzo[g]indol-3-yl)-4-(3-thienyl)-furan-2,5-dione and 1-alkyl- and 1-aryl-3-(5-methoxy-1,2-dimethyl-1H-benzo[g]indol-3-yl-4-(3-thienyl)-1(H)-pyrrole-2,5-diones were synthesized. The substitution of the furandione moiety for pyrroledione gives rise to the radiation and photochemical channels of deactivation of the electron excitation energy of dihetarylethenes. The products of photolysis of pyrrolediones undergo recyclization in both the ground and excited states.