Enantiospecific Formation of <i>Trans</i> 1,3-Disubstituted Tetrahydro-β-carbolines by the Pictet−Spengler Reaction and Conversion of <i>Cis</i> Diastereomers into Their <i>Trans</i> Counterparts by Scission of the C-1/N-2 Bond
作者:Eric D. Cox、Linda K. Hamaker、Jin Li、Peng Yu、Kevin M. Czerwinski、Li Deng、Dennis W. Bennett、James M. Cook、William H. Watson、Mariusz Krawiec
DOI:10.1021/jo951170a
日期:1997.1.1
experiments in TFA. Conversion of the cis diastereomers into the more stable trans diastereomers is believed to occur under acidic conditions by cleavage of the carbon (C-1)-nitrogen (N-2) bond with complete retention of configuration at the C-3 stereocenter. Evidence from deuterium exchange experiments as well as optical rotations support this model for epimerization. In addition, when cis diastereomer