Induction of molecular asymmetry by a remote chiral group

Abstract

Conventional methods of asymmetric synthesis of organic compounds involve the use of either chiral catalysts or stoichiometric amounts of chiral substrates. Invariably, the reacting components must be in close proximity to the entity that introduces chirality^1,2. But supramolecular chemistry^3–5 has shown that stereochemical information can be transmitted through greater distances than are commonly involved in asymmetric syntheses. Here we show that chiral information can be transmitted with remarkable selectivity through as many as nine achiral connecting atoms to give predominantly one diastereomer of a possible four. This contrasts with the general expectation⁶ that a decrease in selectivity would result from an increase in the separation of the chirality-inducing substituent and the reaction site. This ability to convey molecular asymmetry over larger distances should provide access to new chiral molecules that would be difficult to make by conventional methods.