Oxidative cross-couplings between indoles and phenols have been disclosed in the synthesis of benzofuranoindolines , which are key components of complex natural products including diazonamide and phalarine (Figure ). A range of oxidants (including hypervalent iodine reagents , iron(III) salts and electrochemistry ) have been successfully employed in such cross-coupling reactions, some of which demonstrate exceptional levels of cross-coupling selectivity. We reasoned that if the steric bulk on the phenol, and particularly the indole component was increased, the overall process could favour rearomatization rather than [3+2] annulation to generate an atropisomeric heterobiaryl (Figure ). We began by screening a range of oxidants for the reaction between a 1:1.1 mixture of 2-naphthol and 2-methylindole. In a preliminary screen of conditions (see supplementary information S25), hypervalent iodine reagents and VOF3 were poorly selective for the desired heterocoupling process, whilst [Cu(OH)•TMEDA]2Cl2 in air favoured formation of the homocoupled BINOL product. We were delighted to find that catalytic iron(III) chloride in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) with di-tertbutylperoxide as co-oxidant , gave exclusively the cross-coupled heterobiaryl product 3a in 96% yield, as a single indole C-3 regioisomer (Table , entry 1). The remarkable selectivity of this reaction is noteworthy: we do not observe any trace of the potential homocoupled BINOL 4 or 3,3'-bisindole side 5 products. The rotational barrier of this product was determined to be DG ‡ 353K = 26.0 kcal mol -1 ; the potential configurational lability of this material (a class 2 atropisomer) 30 motivated us to continue to investigate compounds with higher rotational barriers. We reasoned that a larger substituent at the C-2 position of the indole would significantly increase the barrier to rotation of the product. Hence, we subjected 2-tert-butylindole to the same reaction conditions; this afforded 39% of the desired heterocoupled product 3b in addition to a 48% yield of the homocoupled BINOL product (Table , entry 2). One strategy to mitigate homocoupling is to modulate the oxidation potential and nucleophilicity of the phenol component through the installation of an electron withdrawing group . When a naphthol bearing a C-3 methyl ester was used in the cross-coupling reaction with 2-tert-butylindole without a large excess of either component, exclusive formation