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Polarographic reduction of 5-hydroxy-7-methoxy flavanone

✍ Scribed by N.R. Bannerjee; H.P. Dahiya

Publisher: Elsevier Science
Year: 1978
Tongue: English
Weight: 241 KB
Volume: 23
Category: Article
ISSN: 0013-4686
DOI: 10.1016/0013-4686(78)87024-8

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✦ Synopsis

Reduction of 5-hydroxy-7-methoxy flavanone in 50% ethanolic buffers pH 1.8-14 follows a similar pattern as that of acetophenones and other aryl carbonyl compounds. The irreversible wave of proton&d form occurring in -acidic media is replaced by a wave oi the unprotonated flavanone in the medium pi-I-range. Decrease of the two-electron wave at pH greater than about 8 is due to a decrease in rate of protonation of the radical anion formed in the first electron uptake. At pH greater than about 10 alkaline cleavage of the flavanone in the bulk of the solution resulted in formation of substituted chalcone, manifested by formation of a more positive polarographic wave and a new absorption band in electronic spectra at 355nm.

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