The invention discloses a compound taking 
cycloheptene as a core and an application of the compound on organic light-emitting devices. The compound has strong rigidity due to the 
cycloheptene structure, and after the compound is connected with a 
carbazole derivative long-chain 
branch structure, the compound has the characteristics of difficult 
crystallization and aggregation performance among molecules, good film-forming property and the like. According to the compound disclosed by the invention, the parent 
nucleus is bipolar, the branched chains are 
electron donating groups, and the electrondonating capacities of the branched chain groups are different, so that the material HOMO energy levels are different, and the compound can be used as materials of different functional 
layers; in addition, the compound provided by the invention has a relatively high 
triplet state energy level, can effectively block 
energy loss, and is beneficial to 
energy transfer. Therefore, after the compound disclosed by the invention is applied to 
OLED devices as an organic electroluminescent functional layer material, the current efficiency, the power efficiency and the external 
quantum efficiency of thedevices are greatly improved; and meanwhile, the service life of the devices is obviously prolonged.