Persistent carbocations from 4,4′-dimethylaminodiphenylethylenes within CaY zeolite: Intrazeolite-water controls the structure of the carbocation

Smriti Koodanjeri, V. Ramamurthy

Research output: Contribution to journalArticle

5 Scopus citations


Inclusion of 4,4′-dimethylaminodiphenylethylene and related olefins within activated CaY results in the formation of persistent monomer carbocations. The structure of the cation, consequently the color of the zeolite, is controlled by water molecules present within zeolites. Under 'dry' conditions the zeolite is light yellow and under 'wet' conditions it is blue colored. Blue color results from the quininoidal structure adopted by 1,1-bis-(4-dimethylaminophenyl)ethyl cation through participation of the lone pair electrons present on the amino substituent at the para position.

Original languageEnglish (US)
Pages (from-to)1615-1618
Number of pages4
JournalTetrahedron Letters
Issue number8
StatePublished - Feb 17 2003
Externally publishedYes



  • Carbocation
  • Diarylethylenes
  • Zeolite

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Drug Discovery

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