Auxiliary induced asymmetric Michael-aldol reaction under kinetic and thermodynamic conditions
摘要:
Asymmetric intramolecular Michael-aldol reaction of (-)-phenylmenthyl enoates 1 affords tricyclic cyclobutanes 2 in excellent diastereoselectivity. It is made clear that Michael-aldol reaction is reversible under conditions using trimethylsilyl iodide (TMSI) in the presence of hexamethyldisilazane (HMDS) at ambient temperature. The difference of stereoselectivity under kinetic or thermodynamic conditions are reported. (C) 2000 Elsevier Science Ltd. Ail rights reserved.
Facile and Stereoselective Access to Nonracemic Tricyclic Cyclobutanes by Asymmetric Intramolecular Michael−Aldol Reaction: Thermodynamic Equilibrium and Activation by Iodonium Ion
作者:Kiyosei Takasu、Megumi Ueno、Masataka Ihara
DOI:10.1021/jo010207q
日期:2001.6.1
Intramolecular Michael-aldol reactions of (-)-phenylmenthyl enoates tethered to cycloalkanone affords tricyclic cyclobutanes with high degrees of diastereochemical control. Kinetic and thermodynamic studies revealed that the Michael-aldol reaction is reversible under conditions in which trimethylsilyl iodide is used in the presence of hexamethyldisilazane at ambient temperature. Different levels of
Auxiliary induced asymmetric Michael-aldol reaction under kinetic and thermodynamic conditions
作者:Kiyosei Takasu、Megumi Ueno、Masataka Ihara
DOI:10.1016/s0040-4039(00)00101-5
日期:2000.3
Asymmetric intramolecular Michael-aldol reaction of (-)-phenylmenthyl enoates 1 affords tricyclic cyclobutanes 2 in excellent diastereoselectivity. It is made clear that Michael-aldol reaction is reversible under conditions using trimethylsilyl iodide (TMSI) in the presence of hexamethyldisilazane (HMDS) at ambient temperature. The difference of stereoselectivity under kinetic or thermodynamic conditions are reported. (C) 2000 Elsevier Science Ltd. Ail rights reserved.