Synthesis And Properties Of Tetrabutadiene And Spirofluorene Derivatives As Organic Electroluminescent Materials

Aggregation Induced Emissions (AIEs) from (Z,Z)-1,1,4,4-tetraarylbutadiene (TPB) and its derivatives are presented in this paper although electroluminescence performances based on TPB have been widely used in recent years. Additionally, a readily and stereoselective synthestic method to (Z,Z)-1,1,4,4-tetraarylbutadiene is provided, and they are characterized by ¹H-NMR, ¹³C-NMR spectroscopy.A series of spiro[3.3]heptane-2,6-di-(2',2",7',7"-tetraiodospirofluorene) is synthesized through cyclization of the 2,7-diiodofluorene with pentaerythrityl bromide in THF under base conditions in middle yields. Subsequent treatment of spiro[3.3]heptane-2,6-di-(2',2",7',7"-tetraiodospirofluorene) with arylboronic acid or arylacetylene under Pd-catalyzed coupling conditions give corresponding spiro[3.3]heptane-2,6-di-(2',2",7',7"-tetraarylspirofluorene), which exhibit excellent violet-blue fluorescence and high thermal stabilities. Based on thermal gravity analysis and luminescence studies, the novel dispirofluorenes derivatives linked by spiro[3.3]heptane core were potentially found to be as emitters in OLED display.