We report a one-pot procedure for
forming a dimeric pyrroloindoline
framework with a thionium reagent. The cyclization of tryptamine with
DMSO and Tf<sub>2</sub>O, followed by substitution with indole derivatives,
produced racemic 3a-indolylpyrroloindolines. The method enables rapid
access to heterodimeric pyrroloindolines as well as to homodimeric
pyrroloindolines

Kazuhiro Higuchi (1696141)