• P D Sarpal

      Articles written in Proceedings – Section A

    • A study of the action of iodine and silver acetate on flavanones

      A C Jain P D Sarpal T R Seshadri

      More Details Abstract Fulltext PDF

      For the action of iodine and silver acetate on flavanones to take place, the nature and position of substituents are important. The presence of either a 5-hydroxyl or a 5-methoxyl is essential for any reaction to occur. A free hydroxyl in the 7-position is inhibitory even for iodination of 5-hydroxyflavanone derivatives. Complete methyl ethers yield 8-iodocompounds; whereas 5-hydroxy-7-methoxyflavanones afford a mixture of 3-iodo and 8-iodo derivatives. Simple 5-hydroxy-flavanone forms 3, 8-di-iodo and 2, 3-di-iodo-5-hydroxy flavanones. 5-Hydroxy-7, 4′-diacetoxy-flavanone undergoes iodination only in the pyranone part to yield 2, 3-di-iodo and 3-iodo derivatives; substitution in the benzene ring is inhibited. It is suggested that the 5-hydroxyl by chelation with the carbonyl increases the activity of the methylene group in the 3-position.

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