A highly abbreviated synthesis of pentalenene by means of the squarate ester cascade.
[reaction: see text] The sequential addition of 5-methylcyclopentyllithium and propynyllithium to diisopropyl squarate results in the efficient formation of a functionalized angular triquinane having two of its five-membered rings substituted precisely as in the target sesquiterpene. Only seven additional steps are then required to access pentalenene.
Paquette
Leo A
LA
Evans Chemical Laboratories, The Ohio State University, Columbus 43210, USA. paquette.1@osu.edu
Geng
Feng
F
D003517:Cyclopentanes / Q000138:chemical synthesis* / Q000737:chemistry; D004952:Esters / Q000737:chemistry*; D015394:Molecular Structure
D003517:Cyclopentanes; D004952:Esters; C024646:pentalenene