Stereodivergent 1,3-difunctionalization of alkenes by charge relocation.

Alkenes are indispensable feedstocks in chemistry. Functionalization at both carbons of the alkene-1,2-difunctionalization-is part of chemistry curricula worldwide 1 . Although difunctionalization at distal positions has been reported 2-4 , it typically relies on designer substrates featuring directing groups and/or stabilizing features, all of which determine the ultimate site of bond formation 5-7 . Here we introduce a method for the direct 1,3-difunctionalization of alkenes, based on a concept termed 'charge relocation', which enables stereodivergent access to 1,3-difunctionalized products of either syn- or anti-configuration from unactivated alkenes, without the need for directing groups or stabilizing features. The usefulness of the approach is demonstrated in the synthesis of the pulmonary toxin 4-ipomeanol and its derivatives.