1-Triflylpyrroles as efficient dienophiles in normal electron demand [4+2] cycloaddition reactions under pressure
作者:Antony Chrétien、Isabelle Chataigner、Serge R. Piettre
DOI:10.1039/b414978e
日期:——
1-Triflylpyrroles bearing acetyl group(s) on position 3, or 2 and 4, are efficient dienophiles in normal electron demand Diels-Alder reactions activated by high pressures and Lewis acids.
Batch versus Flow Photochemistry: A Revealing Comparison of Yield and Productivity
作者:Luke D. Elliott、Jonathan P. Knowles、Paul J. Koovits、Katie G. Maskill、Michael J. Ralph、Guillaume Lejeune、Lee J. Edwards、Richard I. Robinson、Ian R. Clemens、Brian Cox、David D. Pascoe、Guido Koch、Martin Eberle、Malcolm B. Berry、Kevin I. Booker-Milburn
DOI:10.1002/chem.201404347
日期:2014.11.10
The use of flowphotochemistry and its apparent superiority over batch has been reported by a number of groups in recent years. To rigorously determine whether flow does indeed have an advantage over batch, a broad range of synthetic photochemical transformations were optimized in both reactor modes and their yields and productivities compared. Surprisingly, yields were essentially identical in all
Synthesis and Properties of Polyquinolines and Polyanthrazolines Containing Pyrrole Units in the Main Chain
作者:Shifa Hou、Mengxian Ding、Lianxun Gao
DOI:10.1021/ma025768d
日期:2003.6.1
molecular structure, especially pyrrole linkage structures, on the electronic structure, thermodynamics, and some of the optical properties of the polymers were explored. A model of hydrogen bonds in the mainchain of the polymers was suggested to explain the difference in the properties of the isomer polymers. In addition, a polyquinoline (PBM) was chosen to examine the proton conductivity; the result indicated
合成并表征了一系列八种新的在主链上具有吡咯异构体单元的聚喹啉和聚蒽唑啉。新型聚合物显示出高玻璃化转变温度(T g = 242-339°C)和出色的热稳定性(空气中T 5% = 398-536°C,TGA)。相比于系列polyanthrazolines的,该系列聚喹啉表现出更高的热稳定性,更好的溶解度在普通有机溶剂中,并降低最大吸收波长(λ一最大值)。与2,5-吡咯联动Polyanthrazolines显示异常高的λ一个最大值(565纳米)和小的带隙(2.02电子伏特)。溶液中的所有聚合物在10 -2之间的光致发光量子产率低%和10 -5%,激发态寿命为0.28-1.29 ns。探索了分子结构,特别是吡咯键结构,对电子结构,热力学以及聚合物某些光学性质的影响。建议使用聚合物主链中的氢键模型来解释异构体聚合物的性能差异。另外,选择了一种聚喹啉(PBM)来检查质子的电导率。结果表明,PBM / H
Zinc mediated straightforward access to diacylpyrroles
Résumé In this article, we report the preparation of various 2,4- and 2,5-diacylpyrroles via two zinc-mediated acylation reactions of non-protected pyrroles. Supplementary Materials: Supplementary material for this article is supplied as a separate file: mmc1.pdf
Complexity from Simplicity: Tricyclic Aziridines from the Rearrangement of Pyrroles by Batch and Flow Photochemistry
作者:Katie G. Maskill、Jonathan P. Knowles、Luke D. Elliott、Roger W. Alder、Kevin I. Booker-Milburn
DOI:10.1002/anie.201208892
日期:2013.1.28
Molecular acrobatics: Irradiation of N‐butenyl‐substituted pyrroles that bear an electron‐withdrawing group leads to complex tricyclicaziridines through an unprecedented photocycloaddition–rearrangement sequence. Gram quantities of these complex products could be produced by using a bespoke flow reactor (see picture, FEP=fluorinated ethylene propylene).