Formal Synthesis of (+)-Lasubine II and (-)-Subcosine II via Organocatalytic Michael Addition of a Ketone to an α-Nitrostyrene.
The first examples of an organocatalytic Michael addition of a ketone to in situ generated α-nitrostyrenes are reported. A suitably functionalized γ-nitroketone obtained from the organocatalyzed Michael addition was converted into (+)-2-epi-lasubine II, the immediate synthetic precursor of (+)-lasubine II and (-)-subcosine II (enantiomers of the natural quinolizidine alkaloids). Two of the three stereocenters in (+)-2-epi-lasubine II are set by the Michael reaction.
Department of Chemistry, Memorial University , St. John's, Newfoundland, Canada A1B 3X7.
Moorthy
M
N V G
Department of Chemistry, Memorial University , St. John's, Newfoundland, Canada A1B 3X7.
Rajendar
R
Dyapa
Department of Chemistry, Memorial University , St. John's, Newfoundland, Canada A1B 3X7.
Sunil V
SV
Pansare
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D009574:Nitro Compounds / Q000737:chemistry*; D010880:Piperidines / Q000737:chemistry; D054837:Quinolizidines / Q000138:chemical synthesis* / Q000737:chemistry; D011807:Quinolizines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013343:Styrenes / Q000737:chemistry*
D000470:Alkaloids; D007659:Ketones; D009574:Nitro Compounds; D010880:Piperidines; D054837:Quinolizidines; D011807:Quinolizines; D013343:Styrenes; C414385:lasubin I; C000605682:subcosine II