title: A practical synthesis of (+/-)-alpha-isosparteine from a tetraoxobispidine core.
abstract: [reaction: see text] The title alkaloid was synthesized in racemic form from 3,7-diallyl-2,4,6,8-tetraoxo-3,7-diazabicyclo[3.3.1]nonane (7) by a regioselective diallylation reaction followed by double ring-closing olefin metathesis and exhaustive reduction. Tetraoxobispidine 7 was itself prepared in three simple operations from dimethyl malonate. The entire sequence to alpha-isosparteine was conducted on a multigram scale and proceeded without recourse to chromatography.
authors.affiliation: Department of Chemistry, Oregon State University, Corvallis, Oregon 97331-4003, USA. paul.blakemore@science.oregonstate.edu
authors.forename: Paul R
authors.initials: PR
authors.lastname: Blakemore
authors.forename: Colin
authors.initials: C
authors.lastname: Kilner
authors.forename: Neil R
authors.initials: NR
authors.lastname: Norcross
authors.forename: Peter C
authors.initials: PC
authors.lastname: Astles
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D008314:Malonates / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D013034:Sparteine / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D008314:Malonates; C495809:bispidine; D013034:Sparteine; C005230:methyl malonate