4-<i>Endo</i>-<i>T</i><i>rig</i> Cyclization Processes Using Bis(collidine)bromine(I) Hexafluorophosphate as Reagent: Preparation of 2-Oxetanones, 2-Azetidinones, and Oxetanes
作者:Fadi Homsi、Gérard Rousseau
DOI:10.1021/jo9810361
日期:1999.1.1
Reaction in methylene chloride of bis(collidine)bromine(I) hexafluorophosphate with alpha,beta-unsaturated acids and alpha,beta-unsaturated N-sulfonamides was found to lead diastereospecifically to the corresponding 2-oxetanones and 2-azetidinones in moderate yields (23-60%), by an almost unknown 4-endo cyclization. This process allow the synthesis of these interesting classes of products in one step