Improved scope and diastereoselectivity of C–H activation in an expanded supramolecular host

Chiral Ga4L6 assembly Ga4(LN)6 encapsulates cationic iridium half-sandwich complexes that activate aldehyde C–H bonds to form chiral, strongly bound piano-stool complexes. Herein, we report the expanded scope of the larger Ga4(LP)6 host in mediating this transformation. The larger assembly significantly improves both the scope and the diastereoselectivity of this organometallic transformation generally, while substrate-specific interactions demonstrate that host size is an important, but not definitive, factor in determining diastereoselectivity.