Construction of 5
<i>H</i>
‐Dibenzo[
<i>c</i>
,
<i>e</i>
]azepine Framework from Dibenzothiophene Dioxides and
<i>N</i>
‐Benzylimines through S
<sub>N</sub>
Ar Reactions
a mixture of dibenzothiophene dioxides and benzaldehyde N-benzylimines with potassium hexamethyldisilazide induces sequential intermolecular and intramolecular SNAr reactions to eventually form the corresponding 5H-dibenzo[c,e]azepines without any formation of the conceivable five-membered fluorene derivatives.
用六甲基二硅叠氮钾处理二苯并噻吩二氧化物和苯甲醛N-苄亚胺的混合物,诱导连续的分子间和分子内 S N Ar 反应,最终形成相应的 5 H-二苯并 [ c , e ] 氮杂,而不会形成任何可能的五元芴衍生物.
Transition-Metal-Free Synthesis of Carbazoles and Indoles by an S<sub>N</sub>Ar-Based “Aromatic Metamorphosis” of Thiaarenes
dibenzothiophenes, undergo nucleophilic aromatic substitution with anilines intermolecularly and then intramolecularly to yield the corresponding carbazoles in a single operation. The “aromaticmetamorphosis” of dibenzothiophenes into carbazoles does not require any heavy metals. This strategy is also applicable to the synthesis of indoles. Since electron‐deficient thiaarene dioxides exhibit interesting reactivity
通过母体二苯并噻吩的氧化容易制备的二苯并噻吩二氧化物在一次操作中在分子内然后在分子内经历苯胺的亲核芳香取代,然后生成分子内相应的咔唑。二苯并噻吩向咔唑的“芳香变形”不需要任何重金属。该策略也适用于吲哚的合成。由于缺电子的硫杂芳烃二氧化物表现出有趣的反应性,而相应的富电子氮杂芳烃则未观察到,因此,二氧化硫杂ar特定反应与基于S N Ar的芳族变态反应的结合,使得无过渡金属的结构成为可能。难以制备咔唑。
Synthesis of Spirocyclic Diarylfluorenes by One-Pot Twofold S<sub>N</sub>Ar Reactions of Diaryl Sulfones with Diarylmethanes
tetraarylmethanes in a single operation. The transformation would proceed via an intermolecular SNAr reaction of the dioxides with cyclic diarylmethylpotassium followed by intramolecular SNAr cyclization. This straightforward strategy provides a wide range of spirocyclic diarylfluorenes including unusual ones that are otherwise difficult to synthesize.
在KN(SiMe 3)2存在下用环状二芳基甲烷处理二苯并噻吩二氧化物导致在单个操作中形成芴基螺环四芳基甲烷。所述转化将通过二氧化物与环状二芳基甲基钾的分子间S N Ar反应,然后进行分子内S N Ar环化而进行。这种简单的策略可提供多种螺环二芳基芴,包括难于合成的不寻常的螺环。
NEGATIVE DISPERSION RETARDATION PLATE AND ACHROMATIC CIRCULAR POLARIZER
申请人:Geivandov Arthur
公开号:US20120113380A1
公开(公告)日:2012-05-10
The present invention relates generally to the field of organic chemistry and particularly to the nematic lyotropic liquid crystal solution and negative dispersion retardation plate for application in 3D liquid crystal displays. The negative dispersion retardation plate comprises a substrate, and at least one optically anisotropic retardation layer comprising a multi-component guest-host composition coated onto the substrate.