Substituted 1,2,3-triylidenetris(cyanomethanylylidene)) cyclopropanes for vte, electronic devices and semiconducting materials using them

Abstract

The present invention relates to a process for preparation of an electrically doped semiconducting material comprising a [3]-radialene p-dopant or for preparation of an electronic device containing a layer comprising a [3]-radialene p-dopant, the process comprising the steps : (i) loading an evaporation source with the [3]-radialene p-dopant; and (ii) evaporating the [3]-radialene p-dopant at an elevated temperature and at a reduced pressure, wherein the [3]-radialene p-dopant is selected from compounds having a structure according to formula (I) wherein A1 and A2 are independently aryl- or heteroaryl- substituted cyanomethylidene groups, the aryl and / or heteroaryl is selected independently in A1 and A2 from 4-cyano-2,3,5,6-tetrafluorphenyl,2,3,5,6-tetrafluorpyridine-4-yl, 4-trifluormethyl-2,3,5,6-tetrafluorphenyl, 2,4-bis(trifluormethyl)-3,5,6-trifluorphenyl, 2,5-bis(trifluormethyl)-3,4,6-trifluorphenyl, 2,4,6-tris(trifluormethyl)-1,3-diazine-5-yl, 3,4-dicyano-2,5,6-trifluorphenyl, 2-cyano-3,5,6-trifluorpyridine-4-yl, 2-trifluormethyl-3,5,6-trifluorpyridine-4-yl, 2,5,6-trifluor-1,3-diazine-4-yl and 3-trifluormethyl-4-cyano-2,5,6-trifluophenyl), and at least one aryl or heteroaryl is 2,3,5,6-tetrafluorpirydine-4-yl, 2,4-bis(trifluormethyl)-3,5,6-trifluorphenyI, 2,5-bis(trifluormethyl)-3,4,6-trifluorphenyl, 2,4,6-tris(trifluormethyl)-1,3-diazine-5-yl, 3,4-dicyano-2,5,6-trifluorphenyl, 2-cyano-3,5,6-trifluorpyridine-4-yl, 2-trifluormethyl-3,5,6-trifluorphenyl, provided that the heteroaryl in both A1 and A2 cannot be 2,3,5,6-tetrafluorpyridine-4-yl at the same time, respective [3]-radialene compounds, and semiconducting materials and layer, and electronic devices comprising said compounds.

Description

technical field [0001] The present invention relates to aryl or heteroaryl substituted 1,2,3-triylidene tris(cyanomethylidene))cyclopropane (1,2,3-triylidenetris(cyanomethylidene))cyclopropane, which is used in semiconductor electronics Use in devices as p-dopants or hole injection materials, and a robust vacuum thermal evaporation (VTE) process for fabricating such devices. Background technique [0002] It has been found that [3]-axene compounds with cyanomethylene groups substituted with electron-withdrawing aryl or heteroaryl groups are particularly useful as p-dopants for common organic light-emitting diode (OLED) hole-transport materials (HTMs) , see eg US 8 057 712 B2, which is incorporated herein by reference. For industrial production of electronic devices and semiconductor materials using these compounds, a vacuum thermal evaporation (VTE) method is generally used. In existing evaporation sources and in the lower than 10 - 4 At a pressure of Pa, currently used m...

AI Technical Summary

Problems solved by technology

Indeed, the insufficient long-term thermal stability of existing dopants often represents a critical limitation in the length of the production campaign in the mass production of organic electronic devices including electrical dopants

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