Tandem enantioselective conjugate addition--cyclopropanation. Application to natural products synthesis.
A tandem asymmetric conjugate addition-cyclopropanation was developed, in which a cyclic or linear enone was converted to a TMS-protected 3-substituted-cyclopropanol in an efficient one-pot reaction. These compounds were then selectively cleaved to yield alpha-methyl-beta-alkyl ketones, alpha-methylene-enones, or chain extended gamma-alkyl-enones. This methodology was applied to the formal total synthesis of (-)-(S,S)-clavukerin A and (+)-(R,S)-isoclavukerin.
Alexakis
Alexandre
A
Department of Organic Chemistry, University of Geneva, 30 quai Ernest-Ansermet, Switzerland CH-1211.
March
Sébastien
S
D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D003500:Cyclization; D003521:Cyclopropanes / Q000737:chemistry*; D015394:Molecular Structure; D011084:Polycyclic Aromatic Hydrocarbons / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D003521:Cyclopropanes; D011084:Polycyclic Aromatic Hydrocarbons; C473587:clavukerin A; C473586:isoclavukerin; C030797:cyclopropane