Direct Transformation of Terminal Alkynes into Amidines by a Silver-Catalyzed Four-Component Reaction
作者:Binbin Liu、Yongquan Ning、Matteo Virelli、Giuseppe Zanoni、Edward A. Anderson、Xihe Bi
DOI:10.1021/jacs.8b11039
日期:2019.1.30
An unprecedented conversion of terminal alkynes into N-sulfonimidamides (amidines) is reported by a silver-catalyzed, one-pot, four-component reaction with TMSN3, sodium sulfinate, and sulfonylazide. The reaction scope includes both aromatic and aliphatic alkynes. A possible cascade reaction mechanism, consisting of alkyne hydroazidation, sulfonyl radical addition, 1,3-dipolar cycloaddition by TMSN3
Quantitative DNA Interstrand Cross-Link Formation by Coumarin and Thymine: Structure Determination, Sequence Effect, and Fluorescence Detection
作者:Huabing Sun、Heli Fan、Xiaohua Peng
DOI:10.1021/jo5014756
日期:2014.12.5
Quantitative DNA interstrand cross-link (ICL) formation was observed with the coumarin moieties containing a flexible two-carbon or longer chain. DNA cross-linking by coumarins shows a kinetic preference when flanked by an A:T base pair as opposed to a G:C pair. An efficient photoinduced electron transfer between coumarin and dG slows down ICL formation. ICL formation quenches the fluorescence of coumarin
meso-Phenyl-triazole bridged porphyrin-coumarin dyads: Synthesis, characterization and photophysical properties
作者:Dileep Kumar Singh、Mahendra Nath
DOI:10.1016/j.dyepig.2015.05.027
日期:2015.10
Novel zinc (II) meso-phenyl-triazole bridged porphyrin-coumarin dyads have been synthesized in good to excellent yields through copper (I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction of zinc (II) 5-(4-azidophenyl)-10,15,20-triphenylporphyrin with diverse coumarinoalkynes in dimethylformamide containing ascorbic acid at 80 °C. These compounds successfully underwent demetallation in the presence
Synthesis and photophysical properties of β-triazole bridged porphyrin–coumarin dyads
作者:Dileep Kumar Singh、Mahendra Nath
DOI:10.1039/c5ra13955d
日期:——
in the presence of conc. H2SO4 at 0 °C to afford the corresponding free-base porphyrins which on zinc insertion by using Zn(OAc)2·2H2O in a chloroform–methanol mixture at 25 °C produced zinc(II) β-triazole bridged porphyrin–coumarin dyads in good yields. The synthesized products were characterized spectroscopically and evaluated for their photophysical properties by using UV-Vis and fluorescence spectroscopy
通过铜(I)催化的铜(II)2-azido-5,10的惠斯根1,3-偶极环加成反应,合成了新颖的铜(II)β-三唑桥连卟啉-香豆素共轭物。 15,20-四苯基卟啉与各种炔烃取代的香豆素。这些新制备的β-三唑桥连的卟啉-香豆素二联体的铜配合物在浓溶液存在下已成功脱金属。H 2 SO 4在0°C时可提供相应的游离碱卟啉,通过在25°C的氯仿-甲醇混合物中使用Zn(OAc)2 ·2H 2 O在锌中插入锌,可以生成相应的游离锌(II)β-三唑桥连的卟啉-香豆素二聚体,收率很高。对合成的产物进行光谱表征,并通过UV-Vis和荧光光谱评估其光物理性质。初步结果表明,在某些β-三唑桥连的卟啉-香豆素二元组的情况下,从香豆素亚基到卟啉部分的分子内能量转移明显。
Synthesis, characterization and photophysical studies of ß-triazolomethyl-bridged porphyrin-benzo- a-pyrone dyads
作者:DILEEP KUMAR SINGH、MAHENDRA NATH
DOI:10.1007/s12039-016-1058-4
日期:2016.4
A new series of zinc(II) ß-triazolomethyl-bridged porphyrin-benzo- a-pyrone dyads have been synthesized in appreciable yields through a copper(I)-catalyzed “click” reaction of zinc(II) 2-azidomethyl-5,10,15,20-tetraphenylporphyrin with various benzo- a-pyronoalkynes. These novel zinc(II) porphyrin-benzo- a-pyrone dyads successfully underwent demetallation in the presence of concentrated hydrochloric