Abstract
In the synthesis of optically active tryptophan derivatives,
Lewis acid-promoted coupling between indole and optically active
serine-derived aziridine carboxylate is attractive because of the
flexibility and convergence. Scandium perchlorate has been found
to be a superior Lewis acid to the previously reported scandium
triflate with respect to the yields as well as the regioselectivity of
aziridine ring opening. The scope and limitation of this Lewis acid
are also described.
Key words
tryptophan - indole - aziridine - scandium
triflate - scandium perchlorate
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