Recent interest in ionicliquids has developed various uses for them, including some applications by synthetic chemists. Ionicliquids have joined the potential list of non-traditional solvents for Diels–Alderreactions. We report here our own efforts to examine the rates and selectivities of carbon Diels–Alderreactions. Our investigations show that excellent diastereoselective and enantioselective
Enantiomerically pure sultams (+)-4 and (−)-4 were synthesized from tricyclic sultone 1via a four-step reaction sequence. Their uses as newchiralauxiliaries in asymmetric Diels-Alderreactions with diastereoselectivity up to 94:6 are presented.
Asymmetric Desymmetrization of Saturated and Unsaturated meso-1,2-Diols
作者:Hiromichi Fujioka、Yasushi Nagatomi、Naoyuki Kotoku、Hidetoshi Kitagawa、Yasuyuki Kita
DOI:10.1016/s0040-4020(00)00859-0
日期:2000.12
desymmetrization of saturated and unsaturated cyclic and acyclic meso-1,2-diols has been developed from the ene acetals, prepared from the norbornene carboxyaldehyde and meso-1,2-diols. The intramolecular haloetherification of the ene acetals as a key step afforded 8-membered acetals in a stereoselective manner just by the reaction of norbornene olefin even when the ene acetals from unsaturated meso-1,2-diols having
Transesterification of N-acyloxazolidinones with alcohol by lanthanum(III) Iodide
作者:Shin-ichi Fukuzawa、Yuki Hongo
DOI:10.1016/s0040-4039(98)00521-8
日期:1998.5
Transesterification of N-acyloxazolidinones by treatment with an alcohol and lanthanum(III) iodide gives the corresponding esters in good to excellent yields under mild conditions with negligible racemization. (C) 1998 Elsevier Science Ltd. All rights reserved.
Highly Enantioselective Asymmetrization of <i>meso</i>-1,2-Diols through a Novel and Efficient Reaction Cycle
作者:Hiromichi Fujioka、Yasushi Nagatomi、Hidetoshi Kitagawa、Yasuyuki Kita