Diversity-Oriented Approach to Cyclophanes via Fischer Indolization and Ring-Closing Metathesis: Substrate-Controlled Stereochemical Outcome in RCM.

Here, we report a new and diversity-oriented approach to macrocyclic cyclophanes by a Grignard reaction, followed by Fischer indolization and ring-closing metathesis (RCM) as key steps. The configuration of the double bond formed during the RCM depends upon the order of synthetic sequence used. Fischer indolization followed by RCM delivers the cis isomer, whereas RCM followed by Fischer indolization gives the trans isomer.