Nature Chemistry 8, 922–928 (2016); published online 22 August 2016; corrected after print 22 September 2016.

In the version of this Article originally published, in the Figure 2 caption, the HOMO–LUMO gap of the arene, rather than the arenophile, was described as the first requirement for arenophile reactivity. Furthermore, in the caption for Table 3, an oversight resulted in the inclusion of p-TsNH2 as the additive, however, the additive used in this reaction was citric acid (0.5 equiv.); and 2.0 equivalents of NMO were used. This has been corrected in the online versions of this Article.