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Volumn 71, Issue 10, 2006, Pages 3904-3922

Chiral phosphoramide-catalyzed aldol additions of ketone trichlorosilyl enolates. Mechanistic aspects

Author keywords

[No Author keywords available]

Indexed keywords

CATALYSIS; NITROGEN COMPOUNDS; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; REACTION KINETICS; SILICON; SOLVENTS; STEREOCHEMISTRY;

EID: 33646522725     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo060243v     Document Type: Article
Times cited : (66)

References (79)
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    • note
    • All kinetic runs were performed in triplicate to ensure accuracy and reproducibility. See the Supporting Information for complete details.
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    • note
    • It should be noted that methyl ketone derived trichlorosilyl enolates are less reactive than the cyclohexanone derived enolate 4. In a control experiment, the trichlorosilyl enolate derived from methyl n-butyl ketone and 4-phenylbenzaldehyde were stirred at -78 °C for 2 h, providing only 4% of the corresponding aldol adduct, with 95% recovery of the unchanged aldehyde after column chromatography.
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    • note
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    • note
    • Complexes vi and vii also exist as two limiting diastereomeric chair complexes, but will not be considered at this level of analysis.
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    • + the silicon has a half share of 9 electrons). It never has to become a very high energy cationic 7 electron species and remains hypervalent and formally electron rich.
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    • note
    • We have demonstrated a cooperative effect on the stereoselectivity of aldol additions with acyclic trichlrosilyl enolated using tethered phosphoramides: see ref 6b.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.