JP3596261B2 - Phenazacillin compound and organic thin film EL device using the same - Google Patents

Description

【０００９】
下記、式（化１）および（化２）に示す本発明によるフェナザシリン化合物は上記式で表される１０，１０’（５Ｈ，５’Ｈ）−スピロビフェナザシリンの２，２’，８，８’の位置にメチル基を、５の位置にフェニル基、トリル基、またはフェニル基にエチル基、イソプロピル基、ｔ−ブチル基を結合させた基を導入することによって正孔輸送特性を持たせた新規なフェナザシリン化合物であって、可視光領域において無色透明でＴｇが高くかつ成膜性も良好な新規のフェナザシリン化合物である。
【化４】

【化５】

【００１０】
また、式（化３）および（化４）に示す本発明によるフェナザシリン化合物は、５の位置に導入する置換基をよりかさ高いｐ−（ジフェニルアミノ）フェニル基（ｎ＝１の場合）、またはｐ−（ジフェニルアミノ）ビフェニル基（ｎ＝２の場合）とすることにより、式（化１）および（化２）で表されるフェナザシリン化合物よりもそのＴｇが高くなり、より結晶化しにくくすることができる。その他に、５の位置に導入する基としてナフタレン、カルバゾール、ピロール、トリアゾール等を用いることによりキャリア輸送特性を制御することが可能となる。
【００１１】
【発明の実施の形態】
本発明のフェナザシリン化合物の合成では、まず、下記式で表されるジ−ｐ−トリルアミンの２，２’の位置の水素をフッ素、塩素、臭素、ヨウ素などのハロゲン原子で置換した芳香族第２アミンについて、窒素の位置にウルマン反応にてキャリア輸送性、または発光特性を有する置換基を結合させる。続けてハロゲン原子をリチウムで置換した後、四フッ化ケイ素、四塩化ケイ素などのケイ素化合物を加え、リチウムが結合している位置の炭素どうしをケイ素で架橋することにより行われる。
【００１２】
【化６】

【００１３】
このようにして得られたフェナザシリン化合物は真空蒸着法、スピンコート法などの方法により、ＩＴＯなどの電極上に成膜することにより有機薄膜ＥＬ素子の正孔輸送材料として機能する。また、本発明におけるフェナザシリン化合物をポリカーボネイト、ポリエステルなどのバインダー中に分散させた塗液をフタロシアニン等の有機顔料やセレン等の無機材料から成るキャリア発生層上にキャリア輸送層として塗付することにより、電子写真における感光体ドラムとして用いることもできる。
【００１４】
［参考例１］
Ｒ＝ＣＨ_３の式（化２）のフェナザシリン化合物の合成
ジ−ｐ−トリルアミン１００ｇ（０．５０ｍｏｌ）を氷酢酸１０００ｍｌに溶かした溶液を氷冷、攪拌しているところへ臭素１６０ｇ（１．０ｍｏｌ）を氷酢酸６８０ｍｌに溶かした溶液を加えた。反応生成物を亜硫酸水素ナトリウム水溶液で洗浄した後、エタノールから再結晶することにより、無色針状晶として２，２’−ジブロモ−ジ−ｐ−トリルアミンを９８．８ｇ（０．２８ｍｏｌ）単離した。
【００１５】
次に、２，２’−ジブロモ−ジ−ｐ−トリルアミン５４ｇ （０．１５ｍｏｌ ）にｐ−ヨウ化トルエン５０ｇ （０．２３ｍｏｌ ）、無水炭酸カリウム８３．８ｇ （０．６１ｍｏｌ ）、触媒として銅粉１９．７ｇ （０．３１ｍｏｌ ）を加えた混合物をｏ−ジクロロベンゼン４００ｍｌ 中窒素気流下で２０時間還流加熱した。このとき相間移動触媒としてクラウンエーテルを加えてもよい。反応生成物をシリカゲルのカラムで精製することにより、無色アモルファス状物質として２，２’−ジブロモ−ジ−ｐ−トリルアミン４２．１ｇ （９．５ ｘ １０^−２ｍｏｌ ）を得た。
【００１６】
次に、２，２’−ジブロモ−ジ−ｐ−トリルアミン５．０ｇ（１．１ ｘ １０^−２ｍｏｌ ）をジエチルエーテル６０ｍｌに加え、氷冷した。これに、ｎ−ブチルリチウムをヘキサン溶液（１．６ｍｏｌ／ｌ）として１５ｍｌ（２．３ ｘ １０^−２ｍｏｌ ）だけ加え、窒素気流下で１ 時間攪拌した。続けて反応溶液にＳｉＣｌ_４ ０．７ｍｌ （５．６ ｘ １０ ^−３ｍｏｌ）を加え、４５℃で１８時間加熱した。反応生成物をシリカゲルのカラムで精製することにより、白色粉末としてＲ＝ＣＨ_３ の式（化２）のフェナザシリン化合物０．５５ｇ （９．２ ｘ １０^−４ｍｏｌ ）を得た。
【００１７】
本化合物の重クロロホルム溶液について測定した^１ Ｈ−ＮＭＲの結果は次のようになった。
＜^１ Ｈ−ＮＭＲ（ＣＤＣｌ_３ ，ＴＭＳ） σ［ｐｐｍ ］＞
２．１４（１２Ｈ，ＣＨ_３ ）
２．５１（６Ｈ，ＣＨ _３ ）
６．３７−６．４０ （４Ｈ，ＣＨ ）
６．９２−６．９５ （４Ｈ，ＣＨ ）
７．１９−７．２０ （４Ｈ，ＣＨ ）
７．２７−７．２（４Ｈ，ＣＨ ）
７．４５−７．４７ （４Ｈ，ＣＨ ）
【００１８】
本化合物の重クロロホルム溶液の^１３Ｃ−ＮＭＲスペクトルを図１に示す。
【００１９】
ＫＢｒ法にて測定した本化合物のＩＲスペクトルを図２に示す。
【００２０】
ＦＤ法にて本化合物のマススペクトルを測定したところ、分子構造式から推定される分子量と一致するｍ／ｚ ＝５９８ のシグナルが観測された。
【００２１】
本化合物のＤＳＣチャートを図３に示す。ＤＳＣチャートより、本化合物の融点は３２３．５ ℃、Ｔｇは１４４．３ ℃であった。
【００２２】
本化合物の蒸着膜の紫外・可視吸収スペクトルを図４に示す。紫外・可視吸収スペクトルより、４００ｎｍ 以上の可視領域に吸収はなかった。また、理研計器（株）製表面分析計ＡＣ−１にて測定した本化合物の蒸着膜のイオン化ポテンシャルは５．６ｅＶ であった。
【００２３】
【実施例】
［実施例１］
ｎ＝１，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の合成
参考例１で合成した２，２’−ジブロモ−ジ−ｐ−トリルアミン１１ｇ（０．０３ｍｏｌ）にヨードベンゼン９．４ｇ（０．０５ｍｏｌ）、無水炭酸カリウム１７ｇ（０．１２ｍｏｌ）、触媒として銅粉４．０ｇ（０．０６ｍｏｌ）を加えた混合物をｏ−ジクロロベンゼン８０ｍｌ中、窒素気流下で２０時間還流加熱した。このとき相間移動触媒としてクラウンエーテルを加えてもよい。反応生成物をシリカゲルのカラムで精製することにより、無色アモルファス状物質としてＮ−フェニル−２，２’−ジブロモ−ジ−ｐ−トリルアミン４．２ｇ（０．０１ｍｏｌ）を得た。
【００２４】
次に、Ｎ−フェニル−２，２’−ジブロモ−ジ−ｐ−トリルアミン４．０ｇ（９．３ ｘ １０^−３ｍｏｌ ）と酸化第二水銀３．９ｇ（１．８ ｘ １０^−２ｍｏｌ ）およびヨウ素３．３ｇ（１．３ ｘ １０^−２ｍｏｌ ）の混合物をエタノール６４ｍｌに加え、窒素気流下で２時間還流加熱した。反応生成物をシリカゲルのカラムで精製することにより、白色粉末としてＮ−（ｐ−ヨードフェニル）−２，２’−ジブロモ−ジ−ｐ−トリルアミン４．５ｇ（８．１ ｘ １０^−３ｍｏｌ ）を得た。
【００２５】
次に、Ｎ−（ｐ−ヨードフェニル）−２，２’−ジブロモ−ジ−ｐ−トリルアミン４．０ｇ（７．２ ｘ １０^−３ｍｏｌ ）に３−メチルジフェニルアミン１．４ｇ（７．２ ｘ １０^−３ｍｏｌ ）、無水炭酸カリウム２．７ｇ（１．９ ｘ １０^−２ｍｏｌ ）、触媒として銅粉０．６ｇ（９．４ ｘ １０^−３ｍｏｌ ）を加えた混合物をｏ−ジクロロベンゼン１０ｍｌ中、窒素気流下で３２時間還流加熱した。このとき相間移動触媒としてクラウンエーテルを加えてもよい。反応生成物をシリカゲルのカラムで精製することにより、白色粉末としてＮ−［ｐ−（３−メチルジフェニルアミノ）フェニル］−２，２’−ジブロモ−ジ−ｐ−トリルアミン２．８ｇ（４．６ ｘ １０^−３ｍｏｌ ）を得た。
【００２６】
次に、Ｎ−［ｐ−（３−メチルジフェニルアミノ）フェニル］−２，２’−ジブロモ−ジ−ｐ−トリルアミン２．６ｇ（４．３ ｘ １０^−３ｍｏｌ ）をジエチルエーテル６０ｍｌとトルエン１１ｍｌの混合溶媒に加え、氷冷した。これにｎ−ブチルリチウムをヘキサン溶液（１．６ｍｏｌ／ｌ）として５．４ｍｌ （８．５ ｘ １０^−３ｍｏｌ ）だけ加え、窒素気流下で２時間攪拌した。続けて反応溶液にＳｉＣｌ_４ ０．３ｍｌ （２．２ ｘ １０^−３ｍｏｌ ）を加え、４０℃で４０時間加熱した。反応生成物をシリカゲルのカラムで精製することにより、白色粉末としてｎ＝１，Ｒ_１ ＝Ｈ，Ｒ_２ ＝ＣＨ_３ の式（化４）のフェナザシリン化合物０．６ｇ（６．４ ｘ １０^−４ｍｏｌ ）を得た。
【００２７】
本化合物の重クロロホルム溶液について測定した^１ Ｈ−ＮＭＲの結果は次のようになった。
＜^１ Ｈ−ＮＭＲ （ＣＤＣｌ_３ ，ＴＭＳ） σ［ｐｐｍ ］＞
２．１４−２．１５ （１２Ｈ，ＣＨ_３ ）
２．３２−２．３５ （６Ｈ，ＣＨ _３ ）
６．５３−６．５７ （４Ｈ，ＣＨ ）
６．９０−６．９３ （２Ｈ，ＣＨ ）
７．００−７．０２ （４Ｈ，ＣＨ ）
７．０４（２Ｈ，ＣＨ ）
７．０６（２Ｈ，ＣＨ ）
７．０８−７．１０ （４Ｈ，ＣＨ ）
７．１８−７．１９ （４Ｈ，ＣＨ ）
７．２１−７．２３ （４Ｈ，ＣＨ ）
７．２２−７．２５ （２Ｈ，ＣＨ ）
７．２４（２Ｈ，ＣＨ ）
７．２９−７．３１ （４Ｈ，ＣＨ ）
７．３１−７．３５ （４Ｈ，ＣＨ ）
【００２８】
本化合物の重クロロホルム溶液の^１３Ｃ−ＮＭＲスペクトルを図５に示す。
【００２９】
ＫＢｒ法にて測定した本化合物のＩＲスペクトルを図６に示す。
【００３０】
ＦＤ法にて本化合物のマススペクトルを測定したところ、分子構造式から推定される分子量と一致するｍ／ｚ ＝９３２ のシグナルが観測された。
【００３１】
本化合物のＤＳＣチャートを図７に示す。ＤＳＣチャートより、本化合物の融点は３１９．６ ℃、Ｔｇは１５６．０ ℃であった。
【００３２】
本化合物の蒸着膜の紫外・可視吸収スペクトルを図８に示す。紫外・可視吸収スペクトルより、４００ｎｍ 以上の可視領域に吸収はなかった。また、理研計器（株）製表面分析計ＡＣ−１にて測定した本化合物の蒸着膜のイオン化ポテンシャルは５．５ｅＶ であった。
【００３３】
［実施例２］
ｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の合成
参考例１で合成した２，２’−ジブロモ−ジ−ｐ−トリルアミン３．２ｇ（９．１ｘ１０−３ｍｏｌ）にＮ−（４’−ヨードビフェニル−４−イル）−Ｎ−（ｍ−トリルアニリン５．０ｇ（１．１ｘ１０−２ｍｏｌ）、無水炭酸カリウム４ｇ（２．９ｘ１０−２ｍｏｌ）、触媒として銅粉１．０ｇ（１．５ｘ１０−２ｍｏｌ）を加えた混合物をｏ−ジクロロベンゼン２０ｍｌ中、窒素気流下で２８時間還流加熱した。このとき相間移動触媒としてクラウンエーテルを加えてもよい。反応生成物をシリカゲルのカラムで精製することにより、無色アモルファス状物質４．０ｇ（５．８ｘ１０−３ｍｏｌ）を得た。
【００３４】
次に、上記無色アモルファス状物質４．０ｇ（５．８ ｘ １０^−３ｍｏｌ ）をジエチルエーテル８０ｍｌに加え、氷冷した。これにｎ−ブチルリチウムをヘキサン溶液（１．６ｍｏｌ／ｌ）として７．５ｍｌ （１．２ ｘ １０^−２ｍｏｌ ）だけ加え、窒素気流下で１時間攪拌した。続けて反応溶液にＳｉＣｌ_４ ０．３３ｍｌ（２．９ ｘ １０^−３ｍｏｌ ）とトルエン４０ｍｌを加え、６０℃で５０時間加熱した。反応生成物をシリカゲルのカラムで精製することにより、白色粉末としてｎ＝２，Ｒ_１ ＝Ｈ，Ｒ_２ ＝ＣＨ_３ の式（化４）のフェナザシリン化合物０．４ｇ（３．７ ｘ １０^−４ｍｏｌ ）を得た。
【００３５】
本化合物の重クロロホルム溶液について測定した^１ Ｈ−ＮＭＲの結果は次のようになった。
＜^１ Ｈ−ＮＭＲ（ＣＤＣｌ_３ ，ＴＭＳ） σ［ｐｐｍ ］＞
２．１６（１２Ｈ，ＣＨ_３ ）
２．３０（６Ｈ，ＣＨ _３ ）
６．４５−６．４７（４Ｈ，ＣＨ ）
６．８８−７．０７（１２Ｈ，ＣＨ）
７．１５−７．３１ （１８Ｈ，ＣＨ）
７．４４−７．４６（４Ｈ，ＣＨ），
７．６１−７．６３（４Ｈ，ＣＨ）
７．８７−７．８９（４Ｈ，ＣＨ）
【００３６】
本化合物の重クロロホルム溶液の^１３Ｃ−ＮＭＲスペクトルを図９に示す。
【００３７】
ＫＢｒ法にて測定した本化合物のＩＲスペクトルを図１０に示す。
【００３８】
ＦＤ法にて本化合物のマススペクトルを測定したところ、分子構造式から推定される分子量と一致するｍ／ｚ ＝１０８５のシグナルが観測された。
【００３９】
結晶状態の本化合物のＤＳＣチャートを図１１に示す。ＤＳＣチャートより、本化合物の融点は３１０．１ ℃であった。融解後急冷して非晶質状態にした本化合物のＤＳＣチャートを図１２に示す。Ｔｇは１７７．９ ℃であった。
【００４０】
本化合物の蒸着膜の紫外・可視吸収スペクトルを図１３に示す。紫外・可視吸収スペクトルより、４００ｎｍ 以上の可視領域に吸収はなかった。また、理研計器（株）製表面分析計ＡＣ−１にて測定した本化合物の蒸着膜のイオン化ポテンシャルは５．６ｅＶ であった。
【００４１】
［参考例２］
参考例１に記載したフェナザシリン化合物を正孔注入輸送材料として用いた有機薄膜ＥＬ素子（図１４参照）
透明絶縁性の基板（１）として、厚さ１．１ｍｍの青板ガラス板を用い、この上に１２０ｎｍのＩＴＯをスパッタリング法で被覆させ陽極（２）とした。この陽極（２）の上に、第一正孔注入輸送層（３）としてＣｕＰｃを１０ｎｍ真空蒸着し、第二正孔注入輸送層（４）として式（化２）（Ｒ＝ＣＨ_３）を５０ｎｍの厚さで真空蒸着した。
【００４２】
次に、有機電子輸送発光層（５）としてＡｌｑ とキナクリドンを蒸着速度比２００：１で２５ｎｍ蒸着し、最後に陰極（６）としてＭｇとＡｇを蒸着速度比１０：１で３００ｎｍ 蒸着した。
【００４３】
この素子に導線（７）、直流電流（８）を接続したところ、３Ｖ以上の直流電圧により緑色に安定発光し、１３Ｖ では素子の輝度は６９９０ｃｄ／ｍ^２ に達し、本発明の化合物が優れた正孔輸送特性を有することが確かめられた。
【００４４】
［実施例３］
実施例２に記載したフェナザシリン化合物を正孔注入輸送材料として用いた有機薄膜ＥＬ素子（図１４参照）
透明絶縁性の基板（１）として、厚さ１．１ｍｍの青板ガラス板を用い、この上に１２０ｎｍのＩＴＯをスパッタリング法で被覆して陽極（２）とした。この陽極（２）の上に、第一正孔注入輸送層（３）としてＣｕＰｃを１０ｎｍ真空蒸着し、第二正孔注入輸送層（４）として式（化４）（ｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３）を４０ｎｍの厚さで真空蒸着した。
【００４５】
次に、有機電子輸送発光層（５）としてＡｌｑ を５０ｎｍ蒸着し、最後に陰極（６）としてＭｇとＡｇを蒸着速度比１０：１で３００ｎｍ 蒸着した。
【００４６】
この素子に導線（７）、直流電源（８）を接続したところ、４Ｖ 以上の直流電圧により緑色に安定発光し、１ ４Ｖ では素子の輝度は１５０４９ｃｄ／ｍ ^２ に達し、本発明の化合物が優れた正孔輸送特性を有することが確かめられた。
【００４７】
【発明の効果】
本発明の化合物は融点およびＴｇが高く、熱安定性に優れ、かつ成膜性も良好で真空蒸着法またはスピンコート法にて容易に平滑で無色透明なアモルファス状の膜を形成するため、有機薄膜ＥＬ素子や電子写真の分野において耐熱性の高い正孔輸送材料として優れた特性を有している。
【００４８】
【図面の簡単な説明】
【図１】参考例のＲ＝ＣＨ_３の式（化２）のフェナザシリン化合物の１３Ｃ−ＮＭＲスペクトル図である。
【図２】参考例のＲ＝ＣＨ_３の式（化２）のフェナザシリン化合物のＩＲスペクトル図である。
【図３】参考例のＲ＝ＣＨ_３の式（化２）のフェナザシリン化合物のＤＳＣチャート図である。
【図４】参考例のＲ＝ＣＨ_３の式（化２）のフェナザシリン化合物の蒸着膜の紫外・可視吸収スペクトル図である。
【図５】本発明のｎ＝１，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の１３Ｃ−ＮＭＲスペクトル図である。
【図６】本発明のｎ＝１，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物のＩＲスペクトル図である。
【図７】本発明のｎ＝１，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物のＤＳＣチャート図である。
【図８】本発明のｎ＝１，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の蒸着膜の紫外・可視吸収スペクトル図である。
【図９】本発明のｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の１３Ｃ−ＮＭＲスペクトル図である。
【図１０】発明のｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物のＩＲスペクトル図である。
【図１１】結晶状態の本発明のｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物のＤＳＣチャート図である。
【図１２】融解後急冷させた本発明のｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物のＤＳＣチャート図である。
【図１３】本発明のｎ＝２，Ｒ_１＝Ｈ，Ｒ_２＝ＣＨ_３の式（化４）のフェナザシリン化合物の蒸着膜の紫外・可視吸収スペクトル図である。
【図１４】本発明の化合物を正孔輸送層として用いた有機薄膜ＥＬ素子の実施例を示す説明図である。
【符号の説明】
（１）…透明絶縁性基板
（２）…陽極
（３）…第一正孔注入輸送層
（４）…第二正孔注入輸送層
（５）…有機電子輸送発光層
（６）…陰極
（７）…導線
（８）…直流電源[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a novel phenazacillin compound suitable as a hole transport material used in an organic thin film EL device utilizing the electroluminescence (hereinafter abbreviated as EL) phenomenon of an organic thin film.
[0002]
[Prior art]
Eastman Kodak C.I. W. The organic thin-film EL devices developed by Tang et al. Are disclosed in JP-A-59-194393, JP-A-63-264692, JP-A-63-295695, Applied Physics Letter Vol. According to page 913 (1987) and Journal of Applied Physics, Vol. 65, No. 9, page 3610 (1989), etc., generally, an anode, an organic hole injection transport layer, an organic light emitting layer, The organic thin film EL device is constituted in the order of a cathode, and as an organic hole injecting and transporting layer, copper phthalocyanine (hereinafter abbreviated as CuPc), 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, or N, N, N ′, N′-tetra-p-tolyl-1,1′-biphenyl-4,4′-diamine is used as a single layer or a layer deposited by lamination. It was.
[0003]
CuPc used as the organic hole injecting and transporting layer in the above element has high heat resistance, but has high absorption of light in the visible light wavelength region, and is crystalline, and the vapor deposition surface becomes uneven, so only CuPc is used. When used as an organic hole injecting and transporting layer, there was a problem that the efficiency of taking out EL emission was low and that the element was liable to be electrically short-circuited.
[0004]
According to Applied Physics Letter Vol. 57, No. 6, page 531 (1990), Adachi et al. Produced a device having an organic electron injection / transport layer between an organic light emitting layer and a cathode. In this device, N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine (hereinafter abbreviated as TPD) is used as an organic hole injection / transport layer. Glass transition temperature 67 ° C., melting point 159-163 ° C.).
[0005]
The TPD used as the organic hole injecting and transporting layer in the device has an amorphous and smooth vapor-deposited surface and has no light absorption in a visible light wavelength region, but has a melting point and a glass transition temperature (hereinafter, referred to as Tg). (Abbreviated), there was a problem that the element was mixed with the light emitting layer due to heat generated during driving of the element, or the film crystallized with time, and the interface with the light emitting layer became uneven, so that electrical short-circuit was easily caused.
[0006]
[Problems to be solved by the invention]
The present invention has the problems of the hole transporting material in the conventional organic thin film EL element as described above, that is, the problem that the layer made of CuPc having high heat resistance has low light transmittance, and the problem of organic amorphous. The layer composed of TPD can be applied as a hole transporting material that is colorless and transparent in the visible light region and has a high Tg in order to improve the problem that the TPD of TPD has a low Tg and easily deteriorates due to crystallization. The purpose of the present invention is to provide a novel compound.
[0007]
[Means for Solving the Problems]
The present invention has been made in order to solve the above-mentioned problems, and is mainly based on 10,10 ′ (5H, 5′H) -spirobifenazacillin which is bulky and hardly crystallized as shown by the following formula. Skeleton.
[0008]
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[0009]
The phenazacillin compounds according to the present invention represented by the following formulas (Formula 1) and (Formula 2) are 2,2 ′, 8,10,10 ′ (5H, 5′H) -spirobifenazacillin represented by the above formula. By introducing a methyl group at the 8'-position and introducing a phenyl group, tolyl group, or a group obtained by bonding an ethyl group, an isopropyl group, or a t-butyl group to the phenyl group at the 5'-position, to have a hole transporting property. A novel phenazacillin compound which is colorless and transparent in the visible light region, has a high Tg, and has good film formability.
Embedded image

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[0010]
In addition, the phenazacillin compound according to the present invention represented by the formulas (Chem. 3) and (Chem. 4) has a higher p- (diphenylamino) phenyl group (in the case of n = 1) with a bulkier substituent introduced at the 5-position, or By having a p- (diphenylamino) biphenyl group (when n = 2), its Tg is higher than that of the phenazacillin compound represented by the formulas (1) and (2), and the crystallization is more difficult. Can be. In addition, by using naphthalene, carbazole, pyrrole, triazole, or the like as a group to be introduced at the position 5, carrier transport characteristics can be controlled.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
In the synthesis of the phenazacillin compound of the present invention, first, an aromatic second compound in which the hydrogen at position 2,2 ′ of di-p-tolylamine represented by the following formula is substituted with a halogen atom such as fluorine, chlorine, bromine or iodine. With respect to the amine, a substituent having a carrier transporting property or a luminescent property is bonded to the position of nitrogen by an Ullmann reaction. Subsequently, after replacing the halogen atom with lithium, a silicon compound such as silicon tetrafluoride or silicon tetrachloride is added, and the carbon at the position where lithium is bonded is cross-linked with silicon.
[0012]
Embedded image

[0013]
The phenazacillin compound thus obtained functions as a hole transport material of an organic thin film EL device by forming a film on an electrode such as ITO by a method such as a vacuum evaporation method and a spin coating method. Further, by applying a coating liquid in which the phenazacillin compound in the present invention is dispersed in a binder such as polycarbonate and polyester, as a carrier transporting layer on a carrier generating layer composed of an inorganic material such as an organic pigment such as phthalocyanine or selenium, It can also be used as a photosensitive drum in electrophotography.
[0014]
[Reference Example 1]
Synthesis of a phenazacillin compound of the formula (Chemical Formula 2) of R = CH ₃ A solution of 100 g (0.50 mol) of di-p-tolylamine in 1000 ml of glacial acetic acid was cooled with ice and stirred while 160 g (1.0 mol) of bromine was added. ) Was dissolved in 680 ml of glacial acetic acid. The reaction product was washed with an aqueous solution of sodium hydrogen sulfite, and then recrystallized from ethanol to isolate 98.8 g (0.28 mol) of 2,2′-dibromo-di-p-tolylamine as colorless needles. .
[0015]
Next, 50 g (0.23 mol) of p-iodide, 83.8 g (0.61 mol) of anhydrous potassium carbonate, 54 g (0.15 mol) of 2,2'-dibromo-di-p-tolylamine, and copper powder as a catalyst The mixture to which 19.7 g (0.31 mol) was added was heated under reflux in a nitrogen stream in 400 ml of o-dichlorobenzene for 20 hours. At this time, a crown ether may be added as a phase transfer catalyst. The reaction product was purified by a silica gel column to obtain 42.1 g (9.5 × 10 ⁻² mol) of 2,2′-dibromo-di-p-tolylamine as a colorless amorphous substance.
[0016]
Next, 5.0 g (1.1 × 10 ⁻² mol) of 2,2′-dibromo-di-p-tolylamine was added to 60 ml of diethyl ether and cooled with ice. To this, 15 ml (2.3 × 10 ⁻² mol) of n-butyllithium was added as a hexane solution (1.6 mol / l), and the mixture was stirred for 1 hour under a nitrogen stream. Subsequently, 0.7 ml (5.6 × 10 ⁻³ mol) of SiCl ₄ was added to the reaction solution, and the mixture was heated at 45 ° C. for 18 hours. The reaction product was purified by a silica gel column to obtain 0.55 g (9.2 × 10 ⁻⁴ mol) of a phenazacillin compound represented by the formula (Chemical Formula 2) of R = CH ₃ as a white powder.
[0017]
The result of ¹ H-NMR measured for a solution of the present compound in deuterated chloroform was as follows.
< ¹ H-NMR (CDCl ₃ , TMS) σ [ppm]>
2.14 (12H, _CH 3)
2.51 (6H, _CH 3)
6.37-6.40 (4H, CH)
6.92-6.95 (4H, CH)
7.19-7.20 (4H, CH)
7.27-7.2 (4H, CH)
7.45-7.47 (4H, CH)
[0018]
FIG. 1 shows a ¹³ C-NMR spectrum of a heavy chloroform solution of the present compound.
[0019]
FIG. 2 shows the IR spectrum of the compound measured by the KBr method.
[0020]
When the mass spectrum of the present compound was measured by the FD method, a signal of m / z = 598, which coincides with the molecular weight estimated from the molecular structural formula, was observed.
[0021]
FIG. 3 shows a DSC chart of the compound. According to the DSC chart, the melting point of this compound was 323.5 ° C., and the Tg was 144.3 ° C.
[0022]
FIG. 4 shows an ultraviolet-visible absorption spectrum of a vapor deposition film of the present compound. According to the ultraviolet / visible absorption spectrum, there was no absorption in the visible region of 400 nm or more. The ionization potential of the deposited film of the present compound was 5.6 eV as measured by a surface analyzer AC-1 manufactured by Riken Keiki Co., Ltd.
[0023]
【Example】
[Example 1]
Synthesis of a phenazacillin compound of the formula (Formula 4) in which n = 1, R ₁ = H, R ₂ = CH ₃
To 11 g (0.03 mol) of 2,2′-dibromo-di-p-tolylamine synthesized in Reference Example 1 , 9.4 g (0.05 mol) of iodobenzene, 17 g (0.12 mol) of anhydrous potassium carbonate, and copper powder as a catalyst The mixture to which 4.0 g (0.06 mol) was added was refluxed and heated in 80 ml of o-dichlorobenzene under a nitrogen stream for 20 hours. At this time, a crown ether may be added as a phase transfer catalyst. The reaction product was purified by a silica gel column to obtain 4.2 g (0.01 mol) of N-phenyl-2,2'-dibromo-di-p-tolylamine as a colorless amorphous substance.
[0024]
Next, 4.0 g (9.3 × 10 ⁻³ mol) of N-phenyl-2,2′-dibromo-di-p-tolylamine and 3.9 g of mercuric oxide (1.8 × 10 ⁻² mol). A mixture of 3.3 g (1.3 × 10 ⁻² mol) of iodine was added to 64 ml of ethanol, and the mixture was heated under reflux for 2 hours under a nitrogen stream. The reaction product was purified by a silica gel column to give 4.5 g (8.1 × 10 ⁻³ mol) of N- (p-iodophenyl) -2,2′-dibromo-di-p-tolylamine as a white powder. Got.
[0025]
Next, N- (p-iodophenyl) -2,2′-dibromo-di-p-tolylamine (4.0 g, 7.2 × 10 ⁻³ mol) and 3-methyldiphenylamine (1.4 g, 7.2 ×) were used. 10 ⁻³ mol), 2.7 g (1.9 × 10 ⁻² mol) of anhydrous potassium carbonate, and 0.6 g (9.4 × 10 ⁻³ mol) of copper powder as a catalyst were mixed with 10 ml of o-dichlorobenzene. The mixture was refluxed and heated under a nitrogen stream for 32 hours. At this time, a crown ether may be added as a phase transfer catalyst. The reaction product was purified by a silica gel column to give N- [p- (3-methyldiphenylamino) phenyl] -2,2'-dibromo-di-p-tolylamine as a white powder (2.8 g, 4.6 g). x 10 ^-3 mol).
[0026]
Next, 2.6 g (4.3 × 10 ⁻³ mol) of N- [p- (3-methyldiphenylamino) phenyl] -2,2′-dibromo-di-p-tolylamine was added to 60 ml of diethyl ether and 11 ml of toluene. And the mixture was ice-cooled. To this was added only 5.4 ml (8.5 × 10 ⁻³ mol) of n-butyllithium as a hexane solution (1.6 mol / l), and the mixture was stirred under a nitrogen stream for 2 hours. Subsequently, 0.3 ml (2.2 × 10 ⁻³ mol) of SiCl ₄ was added to the reaction solution, and the mixture was heated at 40 ° C. for 40 hours. By purifying the reaction product with a silica gel column, 0.6 g (6.4 × 10 ⁻⁴ ) of a phenazacillin compound of the formula (Formula 4) of n = 1, R ₁ = H, R ₂ = CH ₃ as a white powder. mol).
[0027]
The result of ¹ H-NMR measured for a solution of the present compound in deuterated chloroform was as follows.
< ¹ H-NMR (CDCl ₃ , TMS) σ [ppm]>
2.14-2.15 (12H, _CH 3)
2.32-2.35 (6H, _CH 3)
6.53-6.57 (4H, CH)
6.90-6.93 (2H, CH)
7.00-7.02 (4H, CH)
7.04 (2H, CH)
7.06 (2H, CH)
7.08-7.10 (4H, CH)
7.18-7.19 (4H, CH)
7.21-7.23 (4H, CH)
7.22-7.25 (2H, CH)
7.24 (2H, CH)
7.29-7.31 (4H, CH)
7.31-7.35 (4H, CH)
[0028]
FIG. 5 shows the ¹³ C-NMR spectrum of a heavy chloroform solution of the present compound.
[0029]
FIG. 6 shows the IR spectrum of the compound measured by the KBr method.
[0030]
When the mass spectrum of this compound was measured by the FD method, a signal of m / z = 932, which coincided with the molecular weight estimated from the molecular structural formula, was observed.
[0031]
FIG. 7 shows a DSC chart of the compound. According to the DSC chart, the melting point of this compound was 319.6 ° C., and the Tg was 156.0 ° C.
[0032]
FIG. 8 shows an ultraviolet-visible absorption spectrum of a vapor deposition film of the present compound. According to the ultraviolet / visible absorption spectrum, there was no absorption in the visible region of 400 nm or more. The ionization potential of the deposited film of the present compound was 5.5 eV as measured with a surface analyzer AC-1 manufactured by Riken Keiki Co., Ltd.
[0033]
[ Example 2 ]
Synthesis of a phenazacillin compound of the formula (Formula 4) where n = 2, R ₁ = H, R ₂ = CH ₃
3.2 g (9.1 × 10 −3 mol) of 2,2′-dibromo-di-p-tolylamine synthesized in Reference Example 1 was added to N- (4′-iodobiphenyl-4-yl) -N- (m-tolylaniline). A mixture of 5.0 g (1.1 x 10-2 mol), 4 g (2.9 x 10-2 mol) of anhydrous potassium carbonate, and 1.0 g (1.5 x 10-2 mol) of copper powder as a catalyst was mixed with 20 ml of o-dichlorobenzene in nitrogen. The mixture was heated under reflux for 28 hours under a stream of air, at which time crown ether may be added as a phase transfer catalyst, and the reaction product was purified by a silica gel column to give 4.0 g (5.8 × 10 −3 mol) of a colorless amorphous substance. Got.
[0034]
Next, 4.0 g (5.8 × 10 ⁻³ mol) of the above colorless amorphous substance was added to 80 ml of diethyl ether, and the mixture was cooled with ice. 7.5 ml (1.2 × 10 ⁻² mol) of n-butyllithium as a hexane solution (1.6 mol / l) was added thereto, and the mixture was stirred for 1 hour under a nitrogen stream. Subsequently, 0.33 ml (2.9 × 10 ⁻³ mol) of SiCl ₄ and 40 ml of toluene were added to the reaction solution, and the mixture was heated at 60 ° C. for 50 hours. By purifying the reaction product with a silica gel column, 0.4 g (3.7 × 10 ⁻⁴ ) of the phenazacillin compound of the formula (Formula 4) of n = 2, R ₁ = H, R ₂ = CH ₃ as a white powder. mol).
[0035]
The result of ¹ H-NMR measured for a solution of the present compound in deuterated chloroform was as follows.
< ¹ H-NMR (CDCl ₃ , TMS) σ [ppm]>
2.16 (12H, _CH 3)
2.30 (6H, _CH 3)
6.45-6.47 (4H, CH)
6.88-7.07 (12H, CH)
7.15-7.31 (18H, CH)
7.44-7.46 (4H, CH),
7.61-7.63 (4H, CH)
7.87-7.89 (4H, CH)
[0036]
FIG. 9 shows the ¹³ C-NMR spectrum of a deuterated chloroform solution of the present compound.
[0037]
FIG. 10 shows the IR spectrum of the present compound measured by the KBr method.
[0038]
When the mass spectrum of the present compound was measured by the FD method, a signal of m / z = 11085 which was consistent with the molecular weight estimated from the molecular structural formula was observed.
[0039]
FIG. 11 shows a DSC chart of the present compound in a crystalline state. According to the DSC chart, the melting point of this compound was 310.1 ° C. FIG. 12 shows a DSC chart of the present compound which was rapidly cooled after melting to be in an amorphous state. Tg was 177.9 ° C.
[0040]
FIG. 13 shows an ultraviolet-visible absorption spectrum of a vapor deposition film of the present compound. According to the ultraviolet / visible absorption spectrum, there was no absorption in the visible region of 400 nm or more. The ionization potential of the deposited film of the present compound was 5.6 eV as measured by a surface analyzer AC-1 manufactured by Riken Keiki Co., Ltd.
[0041]
[ Reference Example 2 ]
Organic thin film EL device using the phenazacillin compound described in Reference Example 1 as a hole injection / transport material (see FIG. 14)
As a transparent insulating substrate (1), a blue glass plate having a thickness of 1.1 mm was used, and 120 nm of ITO was coated thereon by a sputtering method to form an anode (2). On this anode (2), CuPc is vacuum-deposited in a thickness of 10 nm as a first hole injection / transport layer (3), and the formula (2) (R = CH ₃ ) is used as a second hole injection / transport layer (4). Vacuum deposited to a thickness of 50 nm.
[0042]
Next, Alq 2 and quinacridone were deposited at a deposition rate of 200: 1 to a thickness of 25 nm as an organic electron transporting and emitting layer (5), and finally Mg and Ag were deposited as a cathode (6) at a deposition rate of 10: 1 to a thickness of 300 nm.
[0043]
When a conducting wire (7) and a direct current (8) were connected to this device, stable green light was emitted by a DC voltage of 3 V or more, and at 13 V, the luminance of the device reached 6990 cd / m ² , and the compound of the present invention was excellent. It was confirmed to have hole transport properties.
[0044]
[Example 3]
Organic thin film EL device using the phenazacillin compound described in Example 2 as a hole injection / transport material (see FIG. 14)
A blue glass plate having a thickness of 1.1 mm was used as a transparent insulating substrate (1), and 120 nm of ITO was coated thereon by a sputtering method to form an anode (2). On this anode (2), CuPc is vacuum-deposited as a first hole injecting and transporting layer (3) to a thickness of 10 nm, and as a second hole injecting and transporting layer (4), the formula (4) (n = 2, R ₁ = H, R ₂ = CH ₃ ) in vacuum with a thickness of 40 nm.
[0045]
Next, 50 nm of Alq was deposited as the organic electron transporting and emitting layer (5), and finally, 300 nm of Mg and Ag were deposited as the cathode (6) at a deposition rate ratio of 10: 1.
[0046]
When a conducting wire (7) and a DC power supply (8) were connected to this device, a stable green light was emitted by a DC voltage of 4 V or more, and the brightness of the device reached 15049 cd / m ² at 14 V, indicating that the compound of the present invention was excellent. It was confirmed to have the hole transporting property.
[0047]
【The invention's effect】
Since the compound of the present invention has a high melting point and Tg, excellent thermal stability, and good film formability, and easily forms a smooth, colorless and transparent amorphous film by a vacuum evaporation method or a spin coating method, the organic compound It has excellent properties as a highly heat-resistant hole transport material in the field of thin film EL devices and electrophotography.
[0048]
[Brief description of the drawings]
FIG. 1 is a 13C-NMR spectrum of a phenazacillin compound of the formula (Formula 2) in which R = CH _{3 in} a reference example .
FIG. 2 is an IR spectrum of a phenazacillin compound of the formula (Formula 2) in which R = CH _{3 according to} a reference example .
FIG. 3 is a DSC chart of a phenazacillin compound of the formula (Formula 2) in which R = CH _{3 in} a reference example .
FIG. 4 is an ultraviolet-visible absorption spectrum of a deposited film of a phenazacillin compound of the formula (Formula 2) in which R = CH _{3 in} a reference example .
FIG. 5 is a 13C-NMR spectrum of a phenazacillin compound of the formula (Formula 4) of the present invention wherein n = 1, R ₁ ＨH, and R ₂ ＣＨCH ₃ .
FIG. 6 is an IR spectrum of the phenazacillin compound of the formula (Formula 4) in which n = 1, R ₁ = H, and R ₂ = CH _{3 according to} the present invention.
FIG. 7 is a DSC chart of the phenazacillin compound of the formula (Formula 4) in which n = 1, R ₁ = H, and R ₂ = CH _{3 according to} the present invention.
FIG. 8 is an ultraviolet-visible absorption spectrum of a vapor-deposited film of a phenazacillin compound of the formula (Formula 4) in which n = 1, R ₁ = H and R ₂ = CH _{3 according to} the present invention.
FIG. 9 is a 13C-NMR spectrum of the phenazacillin compound of the formula (Formula 4) of the present invention wherein n = 2, R ₁ ＨH, and R ₂ ＣＨCH ₃ .
FIG. 10 is an IR spectrum of a phenazacillin compound of the formula (Formula 4) of the invention, in which n = 2, R ₁ = H, and R ₂ = CH ₃ .
FIG. 11 is a DSC chart of a phenazacillin compound of the formula (Formula 4) of the present invention in which n = 2, R ₁ = H, and R ₂ = CH _{3 in} a crystalline state.
FIG. 12 is a DSC chart of a phenazacillin compound of the formula (Formula 4) of n = 2, R ₁ = H, R ₂ = CH ₃ of the present invention, which is cooled rapidly after melting.
FIG. 13 is an ultraviolet-visible absorption spectrum of a vapor-deposited film of a phenazacillin compound of the formula (Formula 4) in which n = 2, R ₁ = H, and R ₂ = CH _{3 according to} the present invention.
FIG. 14 is an explanatory diagram showing an example of an organic thin film EL device using the compound of the present invention as a hole transport layer.
[Explanation of symbols]
(1) ... transparent insulating substrate (2) ... anode (3) ... first hole injection transport layer (4) ... second hole injection transport layer (5) ... organic electron transport light emitting layer (6) ... cathode ( 7) Conductor (8) DC power supply

Claims (3)

A phenazacillin compound represented by the formula (Formula 3).

(Where n is 1 or 2, R ₁ and R ₂ are selected from hydrogen, methyl group, ethyl group, isopropyl group and t-butyl group) A phenazacillin compound represented by the formula (Formula 4).

(Where n is 1 or 2, R ₁ and R ₂ are selected from hydrogen, methyl group, ethyl group, isopropyl group and t-butyl group) 3. An organic thin-film EL device comprising a hole transport material of the organic thin-film EL device, which comprises one of the phenazacillin compounds represented by ( Chem. 3) and ( Chem. 4) according to claim 1 .

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