Glassy 2-(1-benzyl-2-styryl-6-methylpyridin-4(1H)-ylidene) fragment containing 1 H -indene-1,3(2H)-dione and pyrimidine-2,4,6(1H,3H,5H)-trione derivatives with light-emitting and amplified spontaneous emission properties

A series of 2-(1-benzyl-2-(styryl)-6-methylpyridin-4(1H)-ylidene) fragment containing glassy organic compounds have been synthesized from relevant luminescent 4H-pyran-4-ylidene derivatives and investigated as potential solution processable emitters. Glass transition temperatures of synthesized 1H-pyridine compounds are above 100°C with thermal stabilities higher than 260°C. In the solutions of dichloromethane their absorption bands are in the range from 350 nm to 500 nm with photoluminescence from 500 nm to 650 nm. In a contrary to the 4H-pyran-4-ylidene derivatives, the incorporation of various electron acceptor fragments within the 1H-pyridine fragment containing molecules only slightly influenced absorption and photoluminescence band shifts. Based on these compounds, neat spin-cast films were obtained and investigated as light-emitting mediums which show amplified spontaneous emission (ASE) with λmax in the range from 603 nm to 615 nm with ASE threshold values as low as 46 μJ/cm2. Synthesized 1H-pyridine derivatives show perspective to be applied as solution-processable components for light-amplification studies.