Substituent Effects in the Benzofuran System. II. Electrophilic Bromination
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چکیده
منابع مشابه
Electrophilic Aromatic Substitution of Catechins: Bromination and Benzylation
Relative yields of C-6, C-8. and C-6 and C-8 substituted catechins obtained from the reaction of (+ )-catechin or 3' 4',57-tetra-O-methvl-( + )-catechin with pyridinium hydrobromide-perbromide, bromine. p-hydroxybenzyl al~oh~I, or o-hydroxybenZyI alcohol showed differing selectivities depending upon the electrophile used. Ratios of C-6 to C-8 substituted products were 1 : 1.2 for the reaction o...
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The rates of addition of molecular bromine in acetic acid to a number of acetylenes have been found to follow the general equation d(Br,)/dt = [acetylene](k, [Br,] + k3 [Br212 + k,,[Br,] [Br1) In the absence of bromide ion and at low bromine concentrations (< 2 x M), only the k 2 process is observable. These k 2 values for a series of ring-substituted phenylacetylenes are correlated well with o...
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Investigation of the Early Steps in Electrophilic Bromination through the Study of the Reaction with Sterically Encumbered Olefins
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ژورنال
عنوان ژورنال: Bulletin of the Chemical Society of Japan
سال: 1974
ISSN: 0009-2673,1348-0634
DOI: 10.1246/bcsj.47.1267