Diene Cyclization toward Chiral Acyliminium Ions.
نویسندگان
چکیده
منابع مشابه
STEREOSELECTIVE SYNTHESES OF (+)- ISORETRONECANOL AND (+)-5-epi-TASHIROMINE VIA ADDITION OF CHIRAL TITANIUM (IV) ENOLATES TO CYCLIC N-ACYLIMINIUM IONS
The stereoselective addition of the titanium (IV) enolates derived from (S)-4-isopropyl-N-4-chlorobutyryl-1,3-thiazolidine-2-thione (8) and from (S)-4-isopropyl-N-4-chloropentanoyl-1,3-thiazolidine-2-thione (9) to N-Boc-2-methoxypyrrolidine (5b) afforded the addition products (+)-10 and (+)-11 in 84% yield in both cases, as 8.6:1 and 10:1 diastereoisomeric mixtures, respectively. A threestep se...
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Gas phase reactions of mass-selected acylium ions [CH3–C ¢O (1), CH2¢CH–C ¢O (2), C6H5–C ¢O (3), and (CH3)2N–C ¢O (4)] with nitriles (CH3CN, C2H5CN, CH2¢CHCN, and C6H5CN) were investigated using pentaquadrupole multiple-stage mass spectrometry. In analogy with the solution behavior, the ions were found to react readily with benzonitrile by cyclization via double nitrile addition to form aromati...
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ژورنال
عنوان ژورنال: NIPPON KAGAKU KAISHI
سال: 1996
ISSN: 2185-0925,0369-4577
DOI: 10.1246/nikkashi.1996.416