A New and Efficient Access to Oxazoline-5-carboxylates and Amino Acid Derivatives with Cyclopropyl Groups<sup>1</sup>
作者:Marcus W. Nötzel、Markus Tamm、Thomas Labahn、Mathias Noltemeyer、Mazen Es-Sayed、Armin de Meijere
DOI:10.1021/jo990170y
日期:2000.6.1
A Convenient Access to Variously Substituted Spiro[cyclopropane-1,4′-oxazoline]s
作者:Suryakanta Dalai、Mazen Es-Sayed、Marcus Nötzel、Armin de Meijere
DOI:10.1002/ejoc.200800333
日期:2008.7
Michael additions of carboxamides 2a–d under basic conditions onto methyl 2-chloro-2-cyclopropylideneacetate (1) with subsequent ring closure furnished the 4-spirocyclopropanated methyl oxazolinecarboxylates 3a–d (51–81 % yields), from which the corresponding free carboxylic acids 4a–d were obtained by hydrolysis in excellent yield (89–93 %). Coupling reactions of 4a–d with different o-hydroxyaniline