[(3-Cyanopropyl)diisopropylsilyl]acetylene, a More Stable Analogue of [(3-Cyanopropyl)dimethylsilyl]acetylene

Abstract

The preparation and application of a new alkyne protecting group is presented. The reactivity and stability of [(3-cyanopropyl)diisopropylsilyl]acetylene is similar to that of the well-known (triisopropylsilyl)acetylene. Its high polarity simplifies chromatographic separation after coupling to aromatics with more than one reactive site. Moreover, compounds with more than one [(3-cyanopropyl)diisopropylsilyl]acetylene group are easily purified after partial deprotection.

Key words

alkynes - protecting groups - cross-coupling - oligomers - phenylene-ethynylenes

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