Inter- and intramolecular annulation strategies to a cyclopentanone building block containing an all-carbon quaternary stereogenic center

Org Lett. 2015 Mar 20;17(6):1401-4. doi: 10.1021/acs.orglett.5b00207. Epub 2015 Feb 27.


Synthesis of (S)-2-methyl-3-fluorophenyl cyclopentanone methyl ester (1S)-1 has been achieved by both inter- and intramolecular alkylation reactions on multigram scale, using chiral pool reagents. The intramolecular variant is a novel example of a chiral bis-electrophile reacting with a carbon nucleophile to form an enantiomerically pure all-carbon quaternary center.