我们在此首次报道了一种通过“自下而上”的方法将多用途有机催化剂4-(N,N-二甲基氨基)吡啶(DMAP)掺入纳米多孔共轭聚合物(NCP)的网络中。所得的DMAP-NCP材料具有高度浓缩且均匀分布的DMAP催化位点(2.02 mmol g -1)。由于强大的共价键和“自下而上”的单体的刚性,DMAP-NCP还表现出增强的稳定性和永久孔隙率。结果,DMAP-NCP在醇的酰化反应中显示出极好的催化活性,产率为92–99%。该DMAP-NCP可以容易地从反应混合物中回收催化剂,并在至少14个连续循环中重复使用,而活性没有明显的损失。此外,催化酰化反应可以在纯净和连续流动条件下进行至少536小时,且具有相同的催化剂活性。
Photogeneration of Benzhydryl Cations by Near-UV Laser Flash Photolysis of Pyridinium Salts
作者:Tobias A. Nigst、Johannes Ammer、Herbert Mayr
DOI:10.1021/jp3049247
日期:2012.8.23
Laser flash irradiation of substituted N-benzhydryl pyridinium salts yields benzhydryl cations (diarylcarbenium ions) and/or benzhydryl radicals (diarylmethyl radicals). The use of 3,4,5-triamino-substituted pyridines as photoleaving groups allowed us to employ the third harmonic of a Nd/YAG laser (355 nm) for the photogeneration of benzhydryl cations. In this way, benzhydryl cations can also be photogenerated
Two DMAP-based flexible polymernetworks TPB-DMAP and TPA-DMAP have been successfully synthesized via palladium catalyzed Heck cross-coupling. The structures of these polymers were confirmed by solid state 13C CP/MAS and Fourier transform infrared spectroscopy (FTIR). Although both polymers have negligible surface areas, they exhibit excellent catalytic efficiency for the acylation of 1-phenylethanol
通过钯催化的Heck交叉偶联已成功合成了两个基于DMAP的柔性聚合物网络TPB-DMAP和TPA-DMAP。这些聚合物的结构通过固态13 C CP / MAS和傅立叶变换红外光谱(FTIR)进行了确认。尽管两种聚合物的表面积均可以忽略不计,但由于它们具有良好的溶胀能力,因此它们对于1-苯基乙醇与乙酸酐的酰化反应具有极好的催化效率。用作典型催化剂的聚合物TPA-DMAP具有高活性,可将各种醇酰化为相应的酯。此外,该催化剂可以循环至少十次而不会明显损失催化活性。
4-(<i>N</i>,<i>N</i>-Dimethylamino)pyridine-Embedded Nanoporous Conjugated Polymer as a Highly Active Heterogeneous Organocatalyst
作者:Yuan Zhang、Yong Zhang、Ya Lei Sun、Xin Du、Jiao Yi Shi、Wei David Wang、Wei Wang
DOI:10.1002/chem.201103028
日期:2012.5.14
We report herein for the first time the incorporation of a versatile organocatalyst, 4‐(N,N‐dimethylamino)pyridine (DMAP), into the network of a nanoporousconjugatedpolymer (NCP) by the “bottom‐up” approach. The resulting DMAP‐NCP material possesses highly concentrated and homogeneously distributed DMAP catalytic sites (2.02 mmol g−1). DMAP‐NCP also exhibits enhanced stability and permanent porosity
我们在此首次报道了一种通过“自下而上”的方法将多用途有机催化剂4-(N,N-二甲基氨基)吡啶(DMAP)掺入纳米多孔共轭聚合物(NCP)的网络中。所得的DMAP-NCP材料具有高度浓缩且均匀分布的DMAP催化位点(2.02 mmol g -1)。由于强大的共价键和“自下而上”的单体的刚性,DMAP-NCP还表现出增强的稳定性和永久孔隙率。结果,DMAP-NCP在醇的酰化反应中显示出极好的催化活性,产率为92–99%。该DMAP-NCP可以容易地从反应混合物中回收催化剂,并在至少14个连续循环中重复使用,而活性没有明显的损失。此外,催化酰化反应可以在纯净和连续流动条件下进行至少536小时,且具有相同的催化剂活性。
New atropisomeric biaryl derivatives of 4-aminopyridine—identification of an improved nucleophilic catalyst for asymmetric acylation of sec-alcohols
作者:Alan C Spivey、David P Leese、Fujiang Zhu、Stephen G Davey、Richard L Jarvest
DOI:10.1016/j.tet.2004.01.098
日期:2004.5
described. Screening of these enantiomerically pure catalysts, which differ only in the nature of the 4-dialkylamino substituent, for the kinetic resolution of 1-(1-naphthyl)ethanol reveals the importance of this group on the selectivity of catalysis. The di-n-butylamino derivative displays the most favourable catalytic profile. The utility of this catalyst for the kinetic resolution of a selection of sec-alcohols