title: An enantioselective formal synthesis of berkelic acid.
abstract: An enantioselective formal synthesis of berkelic acid is described. The key step involves a late-stage silyl enol ether addition to a benzannulated oxonium ion with subsequent spiroketalization leading to construction of the tetracyclic core. Thermodynamically controlled equilibration under acidic conditions affords the desired spiroketal configuration as a single diastereoisomer.
authors.affiliation: School of Chemical Sciences, The University of Auckland, 23 Symonds Street, Auckland, New Zealand.
authors.forename: Michael C
authors.initials: MC
authors.lastname: McLeod
authors.forename: Zoe E
authors.initials: ZE
authors.lastname: Wilson
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Brimble
mesh_terms: D015394:Molecular Structure; D063065:Organophosphonates / Q000138:chemical synthesis; D013141:Spiro Compounds / Q000138:chemical synthesis*; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D063065:Organophosphonates; D013141:Spiro Compounds; C520589:berkelic acid