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It was possible to functionalize the three fluorobenzyl alcs. and the three 2-(fluorophenyl)ethanols by metalation and subsequent carboxylation, the prototype electrophilic trapping reaction. Triisopropylsilyl (TIPS) outperformed methoxymethyl (MOM) as an ...
Two successive brominations of 8-oxabicyclo[3.2.1]oct-6-en-2-one 6 provided 3-exo,6-exo,7-endo-tribromo-7oxabicyclo[3.2.1]octan-2-endo-one 10 with high stereoselectivity. NaBH4 reduced 10 into 3-exo, 6-exo,7-endo-tribromo-8-oxabicyclo[3.2.1]octan-2-endo-ol ...
Competition expts. have been performed to det. the rates, relative to benzene, with which anisole, the three dimethoxybenzenes and the three trimethoxybenzenes are deprotonated by sec-butyllithium. Only the first substituent (anisole relative to benzene) h ...
Poly(vinylbenzylammonium chloride) (PVBAC) polyelectrolytes possessing defined chain lengths, narrow chain length distributions, uniform charge d., but substituents of different hydrophilicity and size at the quaternary ammonium group were used as model co ...
Eight ethers, nine esters and one ketone were submitted to a systematic structural variation by replacing a hydrogen atom in the vicinity of the oxo function by fluorine and Me. As long as steric factors dominate, a fluorine substituent alters the olfactor ...
Judged by its capacity to promote a hydrogen/metal permutation at an ortho position, the trifluoromethoxy group is superior to both the methoxy and trifluoromethyl groups. Moreover, like CF3 and unlike OCH3, OCF3 exerts a long-range effect that still consi ...
The reactivity of phenolic compounds can be drastically affected by the electronic nature of substituents and by their positions in the aromatic ring. In this work, structure effect on the photoreactivity via TiO2 catalysis is studied using several substit ...
The possibility of using surface-adsorbed monolayers on oxidized GaAs single crystals is investigated to explore liquid crystal (LC) wettability and alignment. A technological process is developed to chemically activate the GaAs surface with a view to perf ...
With reactivity being the most important integral reactor physics quantity - and simultaneously the one that can be measured with the highest accuracy there is a great interest in understanding how possible space- and energy-dependent data and/or modeling ...
