A tetra-substituted chrysene: orientation of multiple electrophilic substitution and use of a tetra-substituted chrysene as a blue emitter for OLEDs

Abstract

The first tetra-substituted non-fused chrysene, 3,6,9,12-tetrakis(4-tert-butylphenyl)chrysene with blue electroluminescence at 450 nm, and with a radiance of 500 cd m(-2), was synthesized by a two-step procedure: direct bromination of chrysene in trimethyl phosphate, followed by palladium-catalyzed cross-coupling of tetrabromochrysene and tert-butylphenylboronic acid .

Chrysene‐Based Blue Emitters

“…[3] Chrysene is aw ell-known PAHw ith blue fluorescence, but its derivatives are sparselye mployed as emitting materiali no ptoelectronic devices due to their low solubility. [4] One possibility to address this issue is the substitution with solubility mediating groupss uch as aryl and alkynyl as well as (electron-rich)a mino substituents, reducing p-p stacking and aggregation. [5] Along this line, severalc hrysene derivatives with high quantum yields were obtained.…”

Domino Friedel–Crafts‐Type Cyclizations of Difluoroalkenes Promoted by the α‐Cation‐Stabilizing Effect of Fluorine: An Efficient Method for Synthesizing Angular PAHs

“…[19] The reaction mixture was allowed to warm to room temperature and stirred for 3 h. Chromatographic purification afforded the indenoindene 5 a, with a 6/ 5/5/6 tetracyclic structure, in 63 % yield, together with an 11 % yield of the 2-benzylindanone 6, which originated from D ( Table 1, entry 1). [7] The formation of 5 a confirmed the successful capture of the second carbocation D. [20] The reaction time was prolonged and the reaction temperature was raised in order to improve the yield of 5 a, but in vain (Table 1, 5,6). TLC analysis showed that 1 a was consumed completely within 10 min at 0 8C.…”

“…[2,3] Phenacenes are promising materials for organic field-effect transistors (OFETs) [4] and blue light-emitting OLEDs. [5] Fluorenes in polymer form have also attracted much attention as materials suitable for OLEDs. [6] However, the lack of a general synthetic method for ortho-fused PAHs with angular (nonlinear) arrangements (angular PAHs) has hampered their development as versatile materials.…”

“…The dehydrogenations of 5 c, 5 d, and 5 h-l proceeded readily on treatment with triphenylmethylium tetrafluoroborate (2.3 equiv, 1,2-dichloroethane, reflux) or palladium on carbon (25 wt %, 10 mol %, mesitylene, reflux) to afford the corresponding [4]helicenes 7 c, 7 d, and 7 h-l in good yields. The benzochrysene 7 m was produced by dehydrogenation of 5 m. [25] The [5]helicene 7 n and the [6]helicene 7 e were also synthesized in a similar manner. [15] Helicenes have classically been synthesized through oxidative photocyclizations of stilbene derivatives.…”

An efficient synthesis of substituted chrysenes

“…[8,9] The two most common synthetic routes to chrysenes are the photochemical cyclisations of styrylnaphthalenes [10] and metal catalysed cyclisations of aromatic acetylenes. [8,11] Our efficient synthesis allows the rapid formation of substituted chrysenes, under simple, benign conditions from readily available commercial materials.…”