Cascade intramolecular carbolithiation

The carbolithiation of unactivated alkenes has also proven very successful for the synthesis of complex polycyclic systems. This has typically been achieved by reaction sequences utilizing an intramolecular carbolithiation process to generate a variety of carbocycles185 and heterocycles186. To achieve the intermolecular carbolithiation reaction required to initiate a controlled cascade reaction sequence for the generation of indole ring scaffold, Kessler and coworkers44 have expanded the synthetic utility of the styrene... 

Intramolecular carbolithiation is now a common process to generate cyclic substrates, and is particularly well suited for the creation of five-membered rings via a 5-exo-trig cyclization [5, 6] (Scheme 1). Cascade reactions can be performed when starting with a diethylenic organoHthium reagent [7]. 

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