Synthesis of 1-[(Triisopropylsilyl)ethynyl]-1λ³,2-benziodoxol-3(1H)-one and Alkynylation of Indoles, Thiophenes, and Anilines

Abstract

An efficient procedure was developed for the synthesis of 1-[(triisopropylsilyl)ethynyl]-1λ³,2-benziodoxol-3(1H)-one on a 100-mmol (36-g) scale. The benziodoxolone can be used for the gold-catalyzed direct alkynylation of indole, 2-hexylthiophene, or N,N-dibenzylaniline on a 5- to 10-mmol scale.

Key words

alkynes - arenes - catalysis - heterocycles - iodine

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