Iridium catalysed C2 site-selective methylation of indoles using a pivaloyl directing group through weak chelation-assistance.

Here we present an iridium catalysed C2-selective methylation of indoles using methyltrifluoroborate as a source of methyl group. The iridium catalyst selectively discriminates the indole C2 and C4 C-H bonds by coordination with a pivaloyl directing group.