Imperial News

Mar 2020 - Article Published in Chemical Science

by Professor Alan C Spivey

Alex Williams' paper on MIDA-derivatives that also direct CH activation at the meta position in aryl boronates is published

Alexander F. Williams, Andrew J. P. White, Alan C. Spivey and Christopher J. Cordier, 'meta-Selective C–H functionalisation of aryl boronic acids directed by a MIDA-derived boronate ester' Chemical Science, 2020, 11, 3301-3306. DOI: 10.1039/D0SC00230E

N-Methyliminodiacetic acid (MIDA) boronates are boronic acid derivatives which are stable to reduction, oxidation and transmetalation. This has led to their widespread use as boronic acid protecting groups (PGs) and in iterative cross-couplings. We describe herein the development of a novel MIDA derivative that acts in a dual manner, as a protecting group and a directing group (DG) for meta C(sp2)–H functionalisation of arylboronic acids. Palladium catalysed C–H alkenylations, acetoxylations and arylations are possible, at room temperature and under aerobic conditions. Deprotection to reveal the functionalised boronic acids is rapid and allows for full recovery of the DG. The technique allows the facile diversification of aryl boronic acids and their subsequent use in a range of reactions or in iterative processes.