Synthesis of a 2,9-dioxabicyclo[3.3.1]nonane via double intramolecular hetero-Michael addition: entry to the F-G ring system of the azaspiracids.
[structure: see text]. An effective approach to form a 1,3-disubstituted 2,9-dioxabicyclo[3.3.1]nonane system representing the core of the F and G rings (C28-C34) of the azaspiracid natural products has been developed. The double intramolecular hetero-Michael addition (DIHMA) of a diol upon an ynone generated the bicyclic ketal in a highly diastereoselective fashion.
Department of Chemistry, University of Minnesota, Minneapolis, Minnesota, Minnesota 55455, USA.
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J
Aiguade
J
J
Hao
C J
CJ
Forsyth
D000473:Alkanes / Q000138:chemical synthesis* / Q000737:chemistry; D001643:Bridged Bicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D007536:Isomerism; D008387:Marine Toxins / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013141:Spiro Compounds / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D000095702:Polyether Toxins
D000473:Alkanes; D001643:Bridged Bicyclo Compounds; D008387:Marine Toxins; D013141:Spiro Compounds; D014867:Water; C429311:2,9-dioxabicyclo(3.3.1)nonane; C406592:azaspiracid; D000095702:Polyether Toxins; C017573:nonane