Progressive Direct Iodination of Sterically Hindered Alkyl Substituted
Benzenes

Abstract

Benzene derivatives bearing at least one bulky alkyl group (i-Pr or t-Bu) were selectively and effectively iodinated using elemental iodine activated by 1-(chloromethyl)-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor^TM, F-TEDA-BF₄). Iodine atoms were progressively introduced at the most electron-rich and sterically less hindered position on the benzene ring. Not more than three iodine atoms could be progressively bonded to a target molecule bearing a i-Pr or t-Bu group.

Key words

iodination - sterically hindered benzenes - Selectfluor^TM (F-TEDA-BF₄)

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