Overcoming Substrate Bias in Radical Addition: Selective C3-Functionalisation of Indoles

Abstract

Radical chemistry provides complementary methods to traditional 2-electron mechanisms for indole functionalisation. Radical addition of electron-poor radicals to indoles is generally C2-selective. We hereby report that this substrate bias can be overcome through installing a bulky silyl group at the indole N–H bond, leading to a strategy for selective addition of electron-poor carbon-centred radicals at the 3-position.

Key words

indole - radical - C3-selective - photochemical - alkylation

• References and Notes

• 1 New address: Organisch-Chemisches Institut, Universität Münster, Corrensstraße 40, 48149 Münster, Germany.
• 2 New address: Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
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