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Catechol (/ ˈ k æ t ɪ tʃ ɒ l / or / ˈ k æ t ɪ k ɒ l /), also known as pyrocatechol or 1,2-dihydroxybenzene, is an organic compound with the molecular formula C 6 H 4 (OH) 2. It is the ortho isomer of the three isomeric benzenediols .
There are three structural isomers: 1,2-dihydroxybenzene (the ortho isomer) is commonly known as catechol, 1,3-dihydroxybenzene (the meta isomer) is commonly known as resorcinol, and 1,4-dihydroxybenzene (the para isomer) is commonly known as hydroquinone. [1]
Fractional crystallisation can be used to obtain pure para product, relying on the principle that it is less soluble than the ortho and thus will crystallise first. Care must be taken to avoid cocrystallisation of the ortho isomer. [2] Many nitro compounds' ortho and para isomers have quite different boiling points. These isomers can often be ...
Substituents add ortho to the amine in diethyl-(meta-trifluoromethyl)aniline and ortho to the fluoride in para-fluorobenzaldehyde; When multiple substituents are comparably activating, steric hindrance dominates regioselectivity. Substituents add ortho to the methyl group in para-(tert-butyl)toluene
There are three main ortho effects in substituted benzene compounds: Steric hindrance forces cause substitution of a chemical group in the ortho position of benzoic acids become stronger acids. Steric inhibition of protonation caused by substitution of anilines to become weaker bases, compared to substitution of isomers in the meta and para ...
In humans, catechol-O-methyltransferase protein is encoded by the COMT gene. [8] Two isoforms of COMT are produced: the soluble short form (S-COMT) and the membrane bound long form (MB-COMT). As the regulation of catecholamines is impaired in a number of medical conditions, several pharmaceutical drugs target COMT to alter its activity and ...
Following a nearly identical reaction scheme as the oxidation of germanium metal with ortho-quinone, dehydration of with catechol ligands results in the same product as the oxidation product, with similar yield 74% on milligram scale and 84% on the gram scale. This particular scheme is of much note since the sole byproduct of this reaction is ...
The catalytic cycle begins with the catechol oxidase in its native oxidized Cu(II)-Cu(II) state with a coordinated hydroxide ion bridging the two copper centers. As catechol enters the active site, a proton is abstracted from one of the alcohols. The catechol coordinates with a Cu(II) center in a monodentate fashion, displacing one of the ...