Synthesis, optical, and thermal properties of glassy trityl group containing luminescent derivatives of 2-tert-butyl-6-methyl-4H-pyran-4-one

In this work we present simple preparation of original trityl group containing glassy luminescent 6-styryl substituted derivatives of 2-(2-tert-butyl-4H-pyran-4-ylidene)malononitrile (DWK-1TB), 2-(2-tert-butyl-4H-pyran-4-ylidene)-2- ethyl-2-cyanoacetate (KWK-1TB), 2-(2-tert-butyl-4H-pyran-4-ylidene)-1H-indene-1,3(2H)-dione (ZWK-1TB) and 5-(2-tert-butyl-4H-pyran-4-ylidene)pyrimidine-2,4,6(1H,3H,5H)-trione (JWK-1TB). Their optical properties have been investigated. The absorption maxima of synthesized glasses is in region from 425 nm to 515 nm and emission maxima is from 470 nm to 625 nm in solution of dichloromethane. But absorption maxima of their solid films is from 425 nm to 500 nm and emission maxima is in range from 570 nm to 710 nm. Incorporation of bulky trityloxy ethyl groups combining with existing tert-butyl groups results in thin solid films formation of synthesized glasses from volatile organic solvents (chloroform, dichloromethane) without them being doped in any polymer. This makes them perspective for potential applications in organic light-emitting diodes and organic lasers by simple luminescent layer composition with cheap wet-casting approaches. All glasses show good thermal stability with thermal decomposition temperatures from 264° to 318°C and glass transition values up to 158°C for DWK-1TB. These thermal properties of synthesized glasses could make them also useful for potential applications in other optical materials such as materials for nonlinear optics.