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Synthesis and Photophysical Properties of Multichromophoric Carbonyl‐Bridged Triarylamines 下载免费PDF全文
Natalie Hammer Dr. Richard Hildner Dr. Milan Kivala Prof. Dr. Jürgen Köhler Prof. Hans‐Werner Schmidt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11708-11718
The synthesis and photophysical properties of two novel multichromophoric compounds is presented. Their molecular design comprises a carbonyl‐bridged triarylamine core and either naphthalimides or 4‐(5‐hexyl‐2,2′‐bithiophene)naphthalimides as second chromophore in the periphery. The lateral chromophores are attached to the core via an amide linkage and a short alkyl spacer. The synthetic approach demonstrates a straightforward functionalization strategy for carbonyl‐bridged triarylamines. Steady‐state and time‐resolved spectroscopic investigations of these compounds, in combination with three reference compounds, provide clear evidence for energy transfer in both multichromophoric compounds. The direction of the energy transfer depends on the lateral chromophore used. Furthermore, the compound bearing the lateral 4‐(bithiophene)naphthaimides is capable of forming fluorescent gels at very low concentrations in the sub‐millimolar regime whilst retaining its energy transfer properties. 相似文献
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The synthesis of a family of N-mustard analogs of S-adenosyl-l-methionine (SAM) containing azides and alkynes at the N6-position of the adenosine base has been accomplished from commercially available inosine. Further biochemical analysis of these analogs indicates successful modification of pUC19 plasmid DNA in an enzyme-dependent fashion with DNA methyltransferases M.TaqI and M.HhaI. 相似文献
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Tiffany N. Thompson Susan Ramos-Hunter Jasmine Robertson Natalie Y. Arnett 《Tetrahedron letters》2013
The effect of solvent purity on the synthesis and yield of bisphenol A tetrachlorocyclotriphosphazene (BATCCP) has not been described in the literature. The purpose of this research was to synthesize BATCCP hybrid monomers and to evaluate the effect of solvent purity on the BATCCP production. BATCCP monomers were prepared by an interfacial procedure in a water/toluene system as a function of time with the assistance of a phase transfer catalyst, tetraoctylammonium bromide. 1H and 31P NMR confirmed the production of BATCCP monomer by the appearance of chemical shifts at 7.18 and 5.35 ppm in the 1H NMR and 23.4 and 13.9 ppm in the 31P NMR, respectively. Distillation of the toluene, not suggested in previous reports of HCCP hybrid synthesis, resulted in an improvement of actual % yield to 40% and stability of the product throughout the 1440 min reaction as confirmed by MALDI, compared with an 11% actual yield at 15 min, decaying to 2% over a 1440 min reaction when the synthesis was performed with ‘anhydrous toluene’ as provided commercially without further distillation. 相似文献
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Andrey A. Fokin Prof. Dr. Boryslav A. Tkachenko Dr. Natalie A. Fokina Dr. Heike Hausmann Dr. Michael Serafin Dr. Jeremy E. P. Dahl Dr. Robert M. K. Carlson Dr. Peter R. Schreiner Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3851-3862
Functionalized nanodiamonds : Various functional groups have been incorporated into the structures of the naturally occurring diamondoids [1(2)3]tetramantane and [12312]hexamantane (cyclohexamantane), which represent hydrogen‐terminated prism‐shaped nanodiamonds (see picture). The attachment points define the use of these diamond‐like molecules as geometric building blocks for a variety of applications.
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Planar 2‐Pyridyl‐1,2,3‐triazole Derived Metallo‐ligands: Self‐assembly with PdCl2 and Photocatalysis
Natalie R. Lagesse Kelvin Y. L. Tan James D. Crowley James A. Findlay 《化学:亚洲杂志》2020,15(10):1567-1573
Self‐assembled metallosupramolecular architectures (MSAs) with built‐in functionalities such as light‐harvesting metal centers are a promising approach for developing emergent properties within discrete molecular systems. Herein we describe the synthesis of two new but simple “click” ligands featuring a bidentate 2‐pyridyl‐1,2,3‐triazole chelate pocket linked to a monodentate pyridyl (either 3‐ or 4‐substituted, L1 and L2 ) unit. The ligands and the corresponding four PdIIand PtIImetallo‐ligands ( Pd1 , Pd2 , Pt1 and Pt2 ) were synthesized and characterized using nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI‐MS), and X‐ray crystallography. Solid‐state characterization of the series of ligands and metallo‐ligands revealed that these compounds display a co‐planar conformation of all the aryl units. The PtIIcontaining metallo‐ligands ( Pt1 and Pt2 ) were found to assemble into square ( Sqr ) and triangular ( Tri ) shaped architectures when combined with neutral PdCl2 linker units. Additionally, the ability of the PtIImetallo‐ligands and Tri to photocatalyze the cycloaddition of singlet oxygen to anthracene was investigated. 相似文献
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Baber RA Charmant JP Cook AJ Farthing NE Haddow MF Norman NC Orpen AG Russell CA Slattery JM 《Dalton transactions (Cambridge, England : 2003)》2005,(19):3137-3139
Treatment of the diborane(4) compound B(2)(NMe(2))(4) with aniline or 2,6-dimethylaniline results in the primary amido compounds B(2)(NHR)(4)(R = Ph, 2,6-Me(2)C(6)H(3)); subsequent treatment with n-BuLi in toluene in each case affords the first examples of anionic imidodiborates namely Li(4)(thf)(6)B(2)(NPh)(4) and Li(4)(thf)(4)B(2)(N-2,6-Me(2)C(6)H(3))(4); all complexes have been characterised crystallographically. 相似文献