Evaluation of N-Aromatic Maleimides as Free Radical Photoinitiators: A Photophysical and Photopolymerization Characterization
作者:Chris W. Miller、E. Sonny Jönsson、Charles E. Hoyle、Kalyanaraman Viswanathan、Edward J. Valente
DOI:10.1021/jp002811v
日期:2001.4.1
Planar N-aromatic maleimides were found to have a low relative excited-state triplet yield, showing significant shift of the primary maleimide UV absorption band with changes in solvent polarity, and did not initiate free radial polymerization upon direct UV excitation. Twisted N-aromatic maleimides have a higher relative triplet yield, show negligible shift of the primary maleimide UV absorption band
Remote Control of Axial Chirality: Aminocatalytic Desymmetrization of <i>N</i>-Arylmaleimides via Vinylogous Michael Addition
作者:Nicola Di Iorio、Paolo Righi、Andrea Mazzanti、Michele Mancinelli、Alessia Ciogli、Giorgio Bencivenni
DOI:10.1021/ja505610k
日期:2014.7.23
Remote control of the axial chirality of N-(2-t-butylphenyl)succinimides was realized via the vinylogous Michael addition of 3-substitutedcyclohexenones to N-(2-t-butylphenyl)maleimides. 9-Amino(9-deoxy)epi-quinine promoted the enantioselective desymmetrization, leading to atropisomeric succinimides with two adjacent stereocenters.
Transparent heat-resistant resin optical material and film
申请人:TOSOH CORPORATION
公开号:US20040063887A1
公开(公告)日:2004-04-01
A transparent heat-resistant resin optical materials having excellent heat resistance and dynamic characteristics, having negative birefringence and exhibiting a high refractive index and a high Abbe number, especially optical compensating members such as films, sheets and retardation films for LCD display element. The transparent heat-resistant resin optical material is made of a copolymer containing a specific olefin residue unit and a specific N-phenyl-substituted maleimide residue unit and having a weight average molecular weight, as reduced into standard polystyrene, of from 5×10
3
to 5×10
6
, the transparent heat-resistant resin optical material exhibiting negative birefringence; and a retardation film having a relationship of three-dimensional refractive indexes of nz≧ny>nx, nz>ny≧nx, or nz>nx≧ny.
Cu-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition of <i>N</i>-2,2,2-Trifluoroethylisatin Ketimines Enables the Desymmetrization of <i>N</i>-Arylmaleimides: Access to Enantioenriched F<sub>3</sub>C-Containing Octahydropyrrolo[3,4-<i>c</i>]pyrroles
With a Cu(OTf)2/chiral ferrocenyl P,N-ligand complex as a catalyst, the enantioselective desymmetrization of N-arylmaleimides was successfully realized by taking advantage of the asymmetric 1,3-dipolar cycloaddition reaction of N-2,2,2-trifluoroethylisatin ketimines. A series of structurally diverse F3C-containing octahydropyrrolo[3,4-c]pyrroles, bearing four contiguous carbon stereocenters and one
以Cu(OTf) 2 /手性二茂铁P,N-配体配合物为催化剂,利用N -2,2的不对称1,3-偶极环加成反应,成功实现了N-芳基马来酰亚胺的对映选择性去对称化, 2-三氟乙基靛红酮亚胺。以优异的结果获得了一系列结构多样的含 F 3 C 八氢吡咯并[3,4- c ]吡咯,具有四个连续的碳立构中心和一个立体手性 C-N 轴向键(产率≤99%,>20:1博士和 99% ee)。
Fullerene C70 as Photoredox Catalyst for the Synthesis of Pyrrolo[2,1‑a]isoquinolines via 1,3‐Dipolar Cycloaddition‐Aromatization Sequence
Metal-free photoredox catalyst C70 was introduced for the facile construction of pyrrolo[2,1-a]isoquinolines under mild conditions, yielding a diverse library of pyrrolo[2,1-a]isoquinolines. Low catalyst loading, gram scale synthesis, and broad substrate scope (48 examples) demonstrate the synthetic utility of the protocol and encourage its future application as a photoredox catalyst in organic transformations
引入无金属光氧化还原催化剂 C 70以在温和条件下轻松构建吡咯并 [2,1-a] 异喹啉,产生多样化的吡咯并 [2,1-a] 异喹啉库。低催化剂载量、克级合成和广泛的底物范围(48 个例子)证明了该协议的综合效用,并鼓励其在未来作为光氧化还原催化剂在有机转化中的应用。