Abstract: The present invention relates to a method of preparing a symmetric or asymmetric cyclic phosphine compound, the method including a step of reacting a cyclic phosphine compound with an organic halogen compound under a predetermined coupling agent. The present invention provides a method of preparing a symmetric or asymmetric cyclic phosphine compound that uses cheaper compounds compared to a conventional method, has excellent economics by stably storing reaction raw materials, improves productivity and yield due to easy reaction control and low generation of by-products, is easily applied on an industrial scale, and has excellent expandability or substitutivity of a synthetic route.

Abstract: The present invention relates to a method of preparing an asymmetric phosphate-based compound. According to the method of the present invention, since a thiolane-based cyclic compound is used alone in a hydrophobic solvent under a base-free condition, the yield of a desired compound may be increased due to excellent reaction stability and reduced side reactions.

Abstract: The present invention relates to a method of preparing a symmetrical phosphate-based compound. According to the method of the present invention, since a dinucleating agent is used in a hydrophobic solvent under a base-free condition, the yield of a desired compound may be increased due to excellent reaction stability and reduced side reactions.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve the lifetime, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve a service life, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve a service life, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve the lifetime, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.