Provided is a 5,6-diaryl-2-pyrazyl triflate, its synthetic method, and a method for synthesizing an organometallic complex having a triarylpyrazine ligand from the 5,6-diaryl-2-pyrazyl triflate. The triflate is readily obtained from the corresponding 5,6-diarylpyrazin-2-ol, and the palladium-catalyzed coupling of the 5,6-diaryl-2-pyrazyl triflate with an arylboronic acid derivative leads to a high yield of a triarylpyrazine derivative having high purity. The use of the triarylpyrazine derivative in the reaction with a metal compound such as a metal chloride results in an ortho-metallated organometallic complex with high purity. The high purity of the organometallic complex contributes to the extremely high durability of a light-emitting element.