In OLEDs, improved efficiency is obtained by using compounds of formula [Ar](CH═CH—R
1
)
n
wherein n is an integer from
1
to
4
; [Ar] is a polycyclic aromatic or heteroaromatic scaffold optionally substituted with one or more alkyl or alkoxy groups; and R
1
is a
5
-membered heteroaryl group optionally substituted with methyl, methoxy, aryl or heteroaryl, or is phenyl or naphthyl optionally substituted with methyl, methoxy, trifluoromethyl or cyano or is biphenyl or substituted biphenyl. The compounds are believed to be novel and can be made by condensing a compound of formula wherein [Ar] and n are as defined above with a compound of formula [Ar](CH
3
)
n
R
1
CHO in the presence of an acid catalyst e.g. an anhydride of an organic acid.
在OLED中,使用公式[Ar](CH═CH—R1)n的化合物可以获得更高的效率,其中n为1至4的整数;[Ar]是一个多环芳香族或杂芳族支架,可选地取代一个或多个烷基或烷氧基;R1是一个5-成员杂芳基团,可选地取代甲基,甲氧基,芳基或杂芳基,或是苯基或
萘基,可选地取代甲基,甲氧基,三
氟甲基或
氰基,或是
联苯或取代
联苯。这些化合物被认为是新颖的,并且可以通过与公式[Ar](
CH3)nR1CHO的化合物在酸催化剂的存在下缩合而制得,例如有机酸的无
水酐。