A5020272528- Coleoptera Taxonomy and Distribution
- Coleoptera: Cerambycidae studies
- Fullerene Chemistry and Applications
- Forest Insect Ecology and Management
- Scarabaeidae Beetle Taxonomy and Biogeography
- Photochromic and Fluorescence Chemistry
- Synthesis and Properties of Aromatic Compounds
- Advanced Polymer Synthesis and Characterization
- Hydrology and Watershed Management Studies
- Olfactory and Sensory Function Studies
- Supramolecular Chemistry and Complexes
- Dendrimers and Hyperbranched Polymers
- Advanced Chemical Physics Studies
- Groundwater flow and contamination studies
- Chemical Synthesis and Analysis
- Analytical Chemistry and Chromatography
- Advanced Chemical Sensor Technologies
- Lipid Membrane Structure and Behavior
- Carbon Nanotubes in Composites
- Molecular Junctions and Nanostructures
- Groundwater and Isotope Geochemistry
- Molecular Sensors and Ion Detection
- Graphene research and applications
- Polydiacetylene-based materials and applications
- Chemical Reactions and Mechanisms
Firmenich (Switzerland)
2014-2024
Natural History Museum Vienna
2020
Forestry and Game Management Research Institute
2020
Humboldt-Universität zu Berlin
1992-2017
German Oceanographic Museum
2016
SAES Group (Italy)
2015
HES-SO Genève
2015
Hanover College
2014
University of Groningen
2012
University of Würzburg
2011
Abstract A fullerene derivative 1 of benzo[18]crown‐6 was obtained by Diels‐Alder addition fullerene[60](C 60 ) to the ortho ‐quinodimethane prepared in situ from 4,5‐bis(bromomethyl)benzo[18]crown‐6 ( 3 with Bu 4 NI toluene. Extraction experiments show that complexation K + ions strongly increases solubility protic solvents like MeOH. Using Langmuir‐Blodgett techniques, monolayers highly amphiphilic fullerene‐derived crown ether and its ion complex were prepared. An X‐ray crystal structure...
A new class of water-soluble, amphiphilic star block copolymers with a large number arms was prepared by sequential atom transfer radical polymerization (ATRP) n-butyl methacrylate (BMA) and poly(ethylene glycol) methyl ether (PEGMA). As the macroinitiator for ATRP, 2-bromoisobutyric acid functionalized fourth-generation hyperbranched polyester (Boltorn H40) used, which allowed preparation polymers that contained on average 20 diblock copolymer arms. The synthetic concept validated AFM...
Serendipitously discovered during electrochemical investigations on the stability of anion 1, a preparatively useful procedure, retro-Bingel reaction, has been identified as method for removing di(alkoxycarbonyl)methano bridges from methanofullerenes. This procedure was applied to prepare first samples enantiomerically pure D2-C76 with unambiguous optical purity.
Abstract Although higher fullerenes are not yet available in larger amounts, their accessibility, like that of C 60 , has gradually improved since the early days fullerence chemistry. Today, many soluble carben can be purchased either pure form or as isomeric mixtures. In particular, 70 is preparative amounts from fullerene soot without need for tedious separation by high‐performance liquid chromatography; this had a major impact on progress chemistry fullerene. Over last years been...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAnalysis of Isomers the Higher Fullerenes by 3He NMR SpectroscopyM. Saunders, H. A. Jimenez-Vazquez, R. J. Cross, W. E. Billups, C. Gesenberg, Gonzalez, Luo, Haddon, F. Diederich, and HerrmannCite this: Am. Chem. Soc. 1995, 117, 36, 9305–9308Publication Date (Print):September 1, 1995Publication History Published online1 May 2002Published inissue 1 September...
Abstract HPLC Separation of higher fullerenes was compared on two different stationary phases, and the preparative isolation pure C 76 is described. Higher‐fullerene derivatives 1 2 were prepared by Diels ‐ Alder reaction 70 with an ortho ‐quinodimethane intermediate generated in situ . Three out four possible isomeric monoadducts, i.e. 1a – c , and, for first time, one monoadduct, 2c could be isolated form characterized H‐NMR, 13 C‐NMR, UV/VIS, mass spectrometry. Five other isomers 2a b d f...
Dynamic mixtures obtained by reversible covalent acylhydrazone formation of fragrance aldehydes and/or ketones and a hydrazide in water were found to be efficient delivery systems for the controlled release highly volatile organic molecules.
In analogy to evolution in biological processes, "molecular evolution", based on the reversible formation of imines, has successfully been explored for drug discovery, receptor design and as a controlled-release vehicle. Multicomponent systems composed amines carbonyl compounds generate structural diversity by reaction different components form equilibrated dynamic mixtures or combinatorial libraries (DCLs). Under thermodynamic control presence an external factor which influences...
Abstract Dynamic mixtures generated by reversible aminal formation efficiently prolong the duration of evaporation bioactive volatile aldehydes. Secondary diamines used for generation dynamic are obtained treatment primary with carbonyl compounds and reduction diimines NaBH 4 . The reversibilities reactions were demonstrated NMR measurements in buffered aqueous solutions. Kinetic rate constants equilibrium hydrolysis aminals determined. performance as delivery systems perfumery ingredients...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 547:257-272 (2016) - DOI: https://doi.org/10.3354/meps11627 Diel and seasonal patterns in acoustic presence foraging behaviour of free-ranging harbour porpoises Tobias Schaffeld1,2,3,*, Stefan Bräger1,4, Anja Gallus1, Michael Dähne1,3, Kathrin Krügel1, Anne Herrmann1, Martin Jabbusch1, Thomas Ruf5, Ursula K....
A novel synthesis is presented of a fourfold ethynyl-substituted perylene diimide dye 4, which acts as core molecule for the buildup polyphenylene dendrimers. Around luminescent first-generation (5), second-generation (6), and third-generation (7) dendritic environment consisting pentaphenylbenzene building blocks are constructed. The dendrimers 5 6 synthesized by an exclusively divergent route, whereas 7, combination convergent approaches applied. Absorption emission spectra 5-7 in...
The pure enantiomers of D2-C84 as well a third constitutional isomer this higher fullerene were produced by retro-Bingel reaction on the first organic derivatives C84 (see scheme). These synthesized Bingel cyclopropenation C84, separated, and unambiguously structurally characterized.
Abstract The synthesis of ( E )‐hex‐3‐ene‐l, 5‐diynes and 3‐methylidenepenta‐1, 4‐diynes with pendant methano[60]‐fullerene moieties as precursors to C 60 ‐substituted poly(triacetylenes) (PTAs, Fig. 1 ) expanded radialenes 2 is described. Bingel reaction diethyl )‐2, 3‐dialkynylbut‐2‐ene‐1, 4‐diyl bis(2‐bromopropane‐dioates) 5 6 two molecules Scheme afforded the monomeric, silyl‐protected PTA 9 10 which, however, could not be effectively desilylated 4 ). Also formed during , well...
The electrochemical properties of covalent derivatives the higher fullerenes C70, C76, C2v-C78, and D3-C78, bearing bis(alkoxycarbonyl)methano addends, were investigated by cyclic voltammetry (CV) and/or steady-state (SSV). Included in this study a series previously prepared mono- to tetrakisadducts monoadducts bis- trisadducts C2v-C78 D3-C78. For all compounds, several (up five) reduction steps one or two oxidation observed. usually required more energy than corresponding processes parent...
Abstract The regioselectivity of multiple cyclopropanations C 70 with 2‐bromopropanedioates in the presence 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as base ( Bingel reaction) was investigated a systematic study. Bisadduct formation occurred preferentially at 66 bonds formed by most pyramidalized sp 2 ‐C‐atoms two opposite poles fullerene and, reaction achiral bis[(ethoxycarbonyl)methyl]2‐bromopropanedioate 13a ), yielded three constitutionally isomeric bis(methano)fullerenes Scheme ). Two...
Abstract The synthesis of the first fullerene cryptate 7 with a sodium ion bound to benzo[2.2.2]cryptand covalently attached methanofullerene[60] is described. amphiphilic properties as well variety other covalent derivatives polar functional groups and ability these compounds form Langmuir monolayers at air‐water interface were investigated in systematic study. Among are Diels‐Alder adducts C 60 methanofullerenes, four which C‐glycosides. films water surface characterized by their pressure...
Abstract Delivery systems generated by reversible hydrazone formation from hydrazine derivatives (see Fig. 1 ) and carbonyl compounds in H 2 O efficiently increase the long‐lastingness of volatile aldehydes ketones (R R CO) various perfumery applications. The hydrazones are usually obtained an ( E configuration at imine double bond (NHNC) and, case aliphatic acylhydrazones R′CONHNCR (R′=alkyl), as syn anti conformers with respect to amide (CONHN). An average free‐energy barrier ca. 78...
Dynamic mixtures generated by reversible aminal formation of fragrance aldehydes with N,N′-dibenzyl alkyldiamines in aqueous systems were found to be suitable delivery for the controlled release bioactive volatiles.
In the presence of alkali metal cations, guanosine-5′-hydrazide (1) forms stable supramolecular hydrogels by selective self-assembly into a G-quartet structure. Besides being physically trapped inside gel structure, biologically active aldehydes or ketones can also reversibly react with free hydrazide functions at periphery to form acylhydrazones. This particularity makes interesting as delivery systems for slow release bioactive carbonyl derivatives. Hydrogels formed from 1 were found be...