Remote control of diastereoselectivity in intramolecular reactions of chiral allylsilanes.
During investigations of cyclization reactions between chiral allylsilanes and N-acyliminium ions, it was discovered that a suitably positioned benzyloxy group on the allylsilane component caused a reversal in the diastereoselectivity of these reactions relative to that normally observed with alkyl-substituted allylsilanes. This effect was subsequently observed in two other reaction types. Investigations into this effect led to the proposal of product formation through thermodynamic control facilitated by neighboring group interactions with a transient cationic species. This hypothesis was experimentally supported by the isolation of an intermediate in the proposed mechanistic pathway.
Judd
Weston R
WR
Department of Medicinal Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Malott Hall, Room 4070, Lawrence, Kansas 66045-7582, USA.
Ban
Sooho
S
Aubé
Jeffrey
J
D000215:Acylation; D000475:Alkenes / Q000737:chemistry*; D000478:Alkylation; D002412:Cations / Q000737:chemistry; D003500:Cyclization; D007097:Imines / Q000737:chemistry*; D007477:Ions / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D012821:Silanes / Q000737:chemistry*; D013237:Stereoisomerism; D013816:Thermodynamics
D000475:Alkenes; D002412:Cations; D007097:Imines; D007477:Ions; D012821:Silanes; C511847:allylsilane