Diastereoselective Synthesis of 4-Substituted L-Prolines by Intramolecular Radical Cyclization of<i>N</i>-Aryl sulphonyl-<i>N</i>-allyl 3-bromoalanines: Interesting Dependence of Selectivity on the Nature of Sulphonamido Groups
作者:Amit Basak、Subhendu Sekhar Bag、Kakali Rani Rudra、Jharna Barman、Sumana Dutta
DOI:10.1246/cl.2002.710
日期:2002.7
Enantiopure 4-substituted L-proline derivatives have been prepared via intramolecular radical cyclization of N-aryl sulphonyl-N-allyl-3-bromo-L-alanines in high yields. Surprisingly, the extent of selectivity was found to be primarily dependent on the nature of sulphonamido aryl group and could be as high as 33:1 using naphthyl sulphonamide.
通过 N-芳基磺酰基-N-烯丙基-3-溴-L-丙氨酸的分子内自由基环化,制备出了高产率的对映纯 4-取代 L-脯氨酸衍生物。令人惊讶的是,研究发现选择性主要取决于磺酰胺基芳基的性质,使用萘磺酰胺时,选择性可高达 33:1。