主链含双层倍半硅氧烷的C_2-对称双脯氨酰胺手性聚合物催化剂的合成及在不对称Aldol反应中的应用

以双夹板形的笼型倍半硅氧烷(DDSQ)和叔丁基氧羰基(Boc)保护的C2-对称双脯氨酰胺为底物,通过硅氢加成反应和脱Boc反应,制得主链含DDSQ的C2-对称双脯氨酰胺手性聚合物催化剂;对其化学结构、分子量及热失重性能进行了表征.将制备的聚合物催化剂应用于催化不对称Aldol反应,探讨了其催化性能.结果表明,催化产物均具有较高的产率和立体选择性,且该催化剂便于分离纯化,循环使用6次后催化活性未见明显下降.

C2-Symmetric Bisprolinamide Chiral Polymer Catalyst with Double Decker Silsesquioxane in Main Chain for the Asymmetric Aldol Reactions

Double-decker silsesquioxane ( DDSQ ) and tert-butyl oxygen carbonyl ( Boc ) protection of C2-symmetric bisprolinamide were used to prepare C2-symmetric bisprolinamide chiral polymer catalyst with DDSQ in the main chain. The chiral polymer catalyst was prepared by silicon hydrogen addition reaction and Boc deprotection. The structure of the prepared polymer catalyst was characterized by means of 1 H NMR, 13 C NMR and 29 Si NMR. The molecular weight and thermal property of the prepared polymer catalyst were characterized by means of GPC and TGA. The polymer catalyst was applied in asymmetric Aldol reaction to study the catalytic function, and the products were obtained in good yields and stereoselectivities. Moreover, the polymer catalyst could be readily recovered and recycled for further transformations at least six cycles with-out observing significant decrease in yield and stereoselectivity.