有效地实现了布朗斯台德酸介导的内烯烃α-氧代乙烯酮二硫缩醛与吡咯的环化反应,得到环戊[ b ]吡咯。一对具有酸强度的布朗斯台德酸,即三氟乙酸和对甲苯磺酸水合物,被用于促进环化反应。生成的产物很容易被间氯过氧苯甲酸氧化成砜。随后用1,8-二氮杂双环[5.4.0]十一碳-7-烯处理得到脱硫的烯烃中间体脱硫的末端烯烃或[2 + 2]环加成产物。本协议提供了在温和条件下易于访问结构多样的环戊[ b ]吡咯衍生物的方法。
BF3·OEt2-mediated alkenylation of pyrroles with α-oxo ketene dithioacetals
作者:Xiaoge Yang、Kaikai Wu、Zhengkun Yu
DOI:10.1016/j.tetlet.2015.05.102
日期:2015.7
BF3·OEt2-mediated alkenylation of pyrroles with α-oxo ketene dithioacetals was efficiently realized, affording mono- and disubstituted ketene pyrrolyl acetals. In the cases of using N-unprotected pyrrole, the reactions gave ketene bipyrrolyl acetals as well as N,O-chelated BF2 complexes. Diverse C–S transformations were achieved for the monosubstituted products, yielding N-heterocycles or multisubstituted
Synthesis and nuclear magnetic resonance spectroscopic studies of 1-arylpyrroles
作者:Chang Kiu Lee、Jung Ho Jun、Ji Sook Yu
DOI:10.1002/jhet.5570370104
日期:2000.1
A series of m- and p-substituted 1-phenyl, 1-benzyl, 1-benzoyl, and 1-(2-phenylethyl)pyrroles was prepared and their 1H and 13C nmr spectroscopic characteristics were examined. In general, good correlations were observed between the chemical shift values of the βH and the βC of pyrroles [except 1-(2-phenylethyl)pyrroles] and the Hammettt σ. The observation may be explained in terms of the electronic
一系列的米-和p -取代的1-苯基,1-苄基,1-苯甲酰基,和1-(2-苯乙基)吡咯制备和它们的1 H和13 C NMR光谱特性进行了研究。一般情况下,被所述β的化学位移值之间观察到良好的相关性H和β吡咯C [除了1-(2-苯乙基)吡咯]和Hammetttσ。可以用取代基的电子效应来解释该观察结果,所述取代基通过吡咯环的βCs与m-和p之间的p轨道相互作用通过键和空间传输。苯环的Cs。还给出了苯环的1 H和13 C化学位移的1-吡咯基,1-吡咯基甲基和1-吡咯基取代基常数。
Decarboxylative formation of N-alkyl pyrroles from 4-hydroxyproline
作者:Indubhusan Deb、Daniel J. Coiro、Daniel Seidel
DOI:10.1039/c1cc11560j
日期:——
N-Alkyl pyrroles are obtained in a single step from 4-hydroxyproline and aldehydes in just 15 min under microwave irradiation.
在微波辐射下,仅用15分钟即可从4-羟基脯氨酸和醛一步获得N-烷基吡咯。
Sustainable Pathways to Pyrroles through Iron-Catalyzed<i>N</i>-Heterocyclization from Unsaturated Diols and Primary Amines
作者:Tao Yan、Katalin Barta
DOI:10.1002/cssc.201600607
日期:2016.9.8
pharmaceutically activecompounds and play an important role in medicinal chemistry. Therefore, the development of new, atom‐economic, and sustainable catalytic strategies to obtain these moieties is highly desired. Direct catalytic pathways that utilize readily available alcohol substrates have been recently established; however, these approaches rely on the use of noble metals such as ruthenium or iridium
Synthesis of N-alkyl pyrroles via decarboxylation/dehydration in neutral ionic liquid under catalyst-free conditions
作者:Veena D. Yadav、Shashikant U. Dighe、Sanjay Batra
DOI:10.1039/c4ra09797a
日期:——
A catalyst-free benign route toN-alkyl pyrroles by reacting aromatic, heteroaromatic or aliphatic aldehydes with 4-hydroxyproline in neutral ionic liquid under microwave irradiation is presented.