Site-selective hexa-hetero-functionalization of α-cyclodextrin an archetypical C6-symmetric concave cycle

Access to C-n (n > 4) symmetric cyclic concave molecules with a different function on each of their n subunits is an unmet challenge. The reason lies in the lack of a post-functionalization method whose site selectivity is sufficiently understood, predictable and modulable to access most functionalization patterns. Here we disclose a new site-directing rule for a debenzylation reaction on cyclodextrins that solves this problem and allows the unprecedented access to penta- and ultimately hexa-differentiations of such C-6 concave cycles. This achievement opens the access to objects with very high-density information.