New long alkyl side-chain benzo[a]phenoxazines as micellisation probes
摘要:
Several novel fluorescent benzo[a]phenoxazinium chlorides possessing a long aliphatic chain substituent at the 5-amino function of the heterocycle were efficiently synthesised. All compounds obtained absorbed and emitted at longer wavelengths with moderate to good fluorescent quantum yields. The photophysics of N-[10-methyl-5-(octylamino)-9H-benzo[a]phenoxazin-9-ylidene]ethanaminium chloride and N-[10-methyl-5-(dodecylamino)-9H-benzo[a]phenoxazin-9-ylidene]ethanaminium chloride was studied in Triton (R) X-100 and in cetyltrimethylammonium bromide micellar media, demonstrating the capability of these fluorophores in detecting the micellisation process. (C) 2009 Elsevier Ltd. All rights reserved.
Highly Reactive, General and Long-Lived Catalysts for Palladium-Catalyzed Amination of Heteroaryl and Aryl Chlorides, Bromides, and Iodides: Scope and Structure–Activity Relationships
作者:Qilong Shen、Tokutaro Ogata、John F. Hartwig
DOI:10.1021/ja077074w
日期:2008.5.1
chelating alkylphosphines for the amination of heteroaryl and aryl chlorides, bromides, and iodides. In the presence of this catalyst, aryl and heteroarylchlorides, bromides, and iodides react with many primary amines in high yields with part-per-million quantities of palladium precursor and ligand. Many reactions of primary amines with both heteroaryl and aryl chlorides, bromides, and iodides occur to
Formal Direct Cross‐Coupling of Phenols with Amines
作者:Zhengwang Chen、Huiying Zeng、Simon A. Girard、Feng Wang、Ning Chen、Chao‐Jun Li
DOI:10.1002/anie.201506751
日期:2015.11.23
The transition‐metal‐catalyzedamination of arylhalides has been the most powerful method for the formation of arylamines over the past decades. Phenols are regarded as ideal alternatives to arylhalides as coupling partners in cross‐couplings. An efficient palladium‐catalyzed formal cross‐coupling of phenols with various amines and anilines has now been developed. A variety of substituted phenols
The Ni-catalyzed cross-coupling reaction between aryl fluorides and primary amines was enabled by the 1,2-bis(dicyclohexylphosphino)benzene (DCYPBz) or 1,2-bis(dicyclohexylphosphino)ethane (DCYPE) ligands. Both N-alkyl- and N-aryl-substituted primary amines participated in the selective reaction to form secondary amines. This protocol would potentially be useful for late-stage diversification of fluorinated
Exploiting Ancillary Ligation To Enable Nickel-Catalyzed C–O Cross-Couplings of Aryl Electrophiles with Aliphatic Alcohols
作者:Preston M. MacQueen、Joseph P. Tassone、Carlos Diaz、Mark Stradiotto
DOI:10.1021/jacs.8b01800
日期:2018.4.18
The use of (L)Ni( o-tolyl)Cl precatalysts (L = PAd-DalPhos or CyPAd-DalPhos) enables the C( sp2)-O cross-coupling of primary, secondary, or tertiary aliphatic alcohols with (hetero)aryl electrophiles, including unprecedented examples of such nickel-catalyzed transformations employing (hetero)aryl chlorides, sulfonates, and pivalates. In addition to offering a competitive alternative to palladium catalysis
Novel long alkyl side chain benzo[a]phenoxazinium chlorides: synthesis, photophysical behaviour and DNA interaction
作者:Carla M.A. Alves、Sarala Naik、Paulo J.G. Coutinho、M. Sameiro T. Gonçalves
DOI:10.1016/j.tet.2009.10.017
日期:2009.12
only that the acid form is observed as coexisting with H-aggregates. The solubility markedly decreased when the chain length increased. The residual ethanol (0.2% v/v) used to facilitate the solubilisation of the benzo[a]phenoxazinium dyes allow for the existence of the basic form in an aqueous solution, possibly through preferential solvation. Photophysical studies in the presence of DNA revealed that
有效地合成了在杂环部分的5位具有丙基,辛基,癸基,十二烷基或十四烷基氨基的几种荧光苯并[ a ]苯恶嗪氯化物。所有化合物的吸收和发射最大值分别在627–638 nm和654–678 nm范围内,并具有良好的荧光量子产率。对它们在乙醇中的光物理性质的研究可以估算酸碱解离常数K a。揭示了随着烷基侧链长度的增加而增强。仅在水性介质中,观察到酸形式与H-聚集体共存。当链长增加时,溶解度显着降低。用于促进苯并[ a ]苯恶嗪鎓染料增溶的残余乙醇(0.2%v / v)可以通过优先溶剂化使碱性形式存在于水溶液中。在存在DNA的情况下进行的光物理研究表明,具有最多8个碳原子的烷基侧链的化合物可以插入DNA核苷酸之间。此外,发现其他形式的DNA结合也是有效的,其中还涉及苯并[ a ]苯恶嗪鎓染料的基本形式。