4-Substituted Prolyl Sulfonamides as Enantioselective Organocatalysts for Aldol Reactions
作者:George Kokotos、Evagelos Bellis、Konstantina Vasilatou
DOI:10.1055/s-2005-870026
日期:——
A series of prolyl and 4-substituted prolyl sulfonamides were prepared and were evaluated as organocatalysts of asymmetric aldol reaction. Using prolyl methanesulfonamide, 4-benzyloxy-pro- lyl methanesulfonamide and toluenesulfonamide and 4-hydroxy- prolyl toluenesulfonamide the aldol product was obtained in much higher enantiomeric excess (ee) in comparison to that observed us- ing proline itself
制备了一系列脯氨酰和4-取代的脯氨酰磺酰胺,并对其作为不对称羟醛反应的有机催化剂进行了评价。使用脯氨酰甲磺酰胺、4-苄氧基-脯氨酰甲磺酰胺和甲苯磺酰胺和 4-羟基脯氨酰甲苯磺酰胺,与使用脯氨酸本身观察到的相比,得到的羟醛产物对映体过量 (ee) 要高得多。此外,这些新催化剂的使用量可能低于脯氨酸,因为它们在有机溶剂中的溶解度有所提高。