Organometallics in organic synthesis. Applications of a new diorganozinc reaction to the synthesis of C-glycosyl compounds with evidence for an oxonium-ion mechanism.
The mechanistic and stereochemical features of a new organozinc-based substitution process [heteroatom-C-(R1,R2)-SPh + R3(2)Zn----heteroatom-C-(R1,R2,R3)], first discovered during a total synthesis of the alkaloid mycotoxin alpha-cyclopiazonic acid, are described. Phenyl thioglycosides were valuable substrates in studying the nature of this reaction process. Since these sulfur compounds are converted into C-glycosyl compounds with some degree of stereoselectivity, the organozinc chemistry does provide a new entry to these biologically active substances.
University of Pittsburgh, Department of Chemistry, Pennsylvania 15260.
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Kozikowski
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Konoike
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Ritter
D006027:Glycosides / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009942:Organometallic Compounds; D013055:Spectrophotometry, Infrared; D013329:Structure-Activity Relationship; D015032:Zinc
D006027:Glycosides; D007202:Indicators and Reagents; D009942:Organometallic Compounds; D015032:Zinc