High-contrast fluorescence sensing of aqueous Cu(<scp>i</scp>) with triarylpyrazoline probes: dissecting the roles of ligand donor strength and excited state proton transfer
作者:M. Thomas Morgan、Pritha Bagchi、Christoph J. Fahrni
DOI:10.1039/c2dt31985c
日期:——
Cu(I) probes in methanol, we integrated the arylamine PET donor into the backbone of a hydrophilic thiazacrown ligand with a sulfonated triarylpyrazoline as a water-soluble fluorescence reporter. This approach was not only expected to disfavor ternary complex formation in aqueous solution but also to maximize PET switching through a synergistic Cu(I)-induced conformational change. The resulting water-soluble
基于光诱导电子转移 (PET) 机制的Cu( I ) 响应荧光探针通常显示相对于荧光报告基因的固有量子产率不完全的荧光恢复。以前对带有N-芳基噻唑基冠 Cu( I )-受体的探针的研究表明,不完全的 Cu( I )-N 配位和由此产生的与溶剂分子形成的三元复合物会影响回收率。基于成功增加 Cu( I ) 探针的荧光对比度和量子产率的策略甲醇,我们将芳胺 PET 供体整合到亲水性噻唑冠配体的骨架中,磺化三芳基吡唑啉作为水溶性荧光报告分子。这种方法不仅不利于水溶液中三元复合物的形成,而且还通过协同的 Cu( I ) 诱导的构象变化来最大化 PET 转换。得到的水溶性探针1在被 Cu( I )饱和后产生了 57 倍的强荧光增强,对其他阳离子,包括 Cu( II )、Hg( II ) 和 Cd( II )具有高选择性;然而,与原始N 的探针相比,恢复量子产率并未提高-芳基噻唑冠设计。从详细的光物理
An aryne triggered ring-opening fluorination of cyclic thioethers with potassium fluoride
作者:Rong Fan、Binbin Liu、Tianyu Zheng、Kun Xu、Chen Tan、Tianlong Zeng、Shuaisong Su、Jiajing Tan
DOI:10.1039/c8cc03766c
日期:——
report an aryne triggered ring-opening fluorination protocol of a great variety of saturated sulfur heterocycles. A key factor for the success is the identification of a suitable mediator. Compared to previous methods, this transition-metal free protocol employs low-cost potassium fluoride as the fluorine source. The operational simplicity and mild reaction conditions allow for the rapid synthesis of a
Copper-Catalyzed Oxyalkynylation of C–S Bonds in Thiiranes and Thiethanes with Hypervalent Iodine Reagents
作者:Julien Borrel、Guillaume Pisella、Jerome Waser
DOI:10.1021/acs.orglett.9b04157
日期:2020.1.17
We report the oxyalkynylation of thiiranes and thietanes using ethynylbenziodoxolonereagents (EBXs) to readily access functionalized building blocks bearing an alkynyl, a benzoate, and an iodide group. The reaction proceeds with high atom efficiency most likely through an alkynyl-episulfonium intermediate. The transformation is copper-catalyzed and compatible with a large array of thiiranes and thietanes
Organosulfides are a common class of structure units in bioactive molecules and functional materials motivating continuous developments of efficient synthetic methods. Herein, we report an electrophilic aryne-activated ringopening protocol of one or two heteroatom containing saturated sulfur heterocycles. This three-component transformation proceeds under mild reaction conditions and displays exceptional
New thymine thietanenucleosides 7 and 20 were synthesized viaPummerer rearrangement of the corresponding sulfoxides 5 and 18 in the presence of thymine, TMSOTf, Et3N, and ZnI2 as a keystep.