作者:Rakeshwar B. Chhor、Bernd Nosse、Sebastian Sörgel、Claudius Böhm、Michael Seitz、Oliver Reiser
DOI:10.1002/chem.200390019
日期:2003.1.3
development of a new method for the enantioselective synthesis of disubstituted gamma-butyrolactones is reported. Based on this strategy, the totalsynthesis of three paraconic acids, that is (-)-roccellaricacid, (-)-nephrosteranicacid and (-)-protopraesorediosic acid, and the formal totalsynthesis of (-)-methylenolactocin and (-)-protolichesterinic acid is described, which are important because of their
The diastereo- and enantioselective cyclopropanation of furans was achieved in up to 91% ee using a new set of chiral bis(oxazoline) ligands that are able to use secondary binding sites to enhance selectivity. In contrast, with substrates such as styrene and N-Boc-pyrrole, with which no secondary interactions with the ligands can occur, only moderate selectivities (<50% ee) were achieved. (C) 2003 Elsevier Science Ltd. All rights reserved.