6533b851fe1ef96bd12a8c93
RESEARCH PRODUCT
Kinetik der Bromierung von Phenolen und phenolischen Mehrkernverbindungen, 5. Mitt.
Klaus BeismannWalter VogtVolker BöhmerDiethard Stotzsubject
Reaction ratechemistry.chemical_compoundAcetic acidChemistryHydrogen bondIntramolecular forceKinetic isotope effectHalogenationOrganic chemistryMoleculeGeneral ChemistryPhenolsMedicinal chemistrydescription
The kinetics of the bromination of six differently substituted 2,6-bis(hydroxybenzyl)phenols having only one reactivepara position at the phenolic unit in the middle of the molecule were studied in acetic acid at 22°C. The reaction rate decreases if intramolecular hydrogen bonds between one or two hydroxy groups of the adjacent phenolic units and the hydroxy group of the reacting unit become possible, and it is especially low, if these hydrogen bonds are directed to the middle by bulky substituents inortho position. This must be explained by a smaller +M-effect of the hydroxy group of the reacting unit. A kinetic isotope effect is observed in deutero acetic acid, where the reaction rate is decreased by the same amount for compounds with and without intramolecular hydrogen bonds.
year | journal | country | edition | language |
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1984-01-01 | Monatshefte f�r Chemie Chemical Monthly |