制备了具有双氢电位的脯氨酰胺,并将其用作不对称羟醛反应的有机催化剂。含有金刚烷的催化剂显示出改进的催化活性,通过使用盐水作为溶剂进一步增强了催化活性。在 0 °C 的盐水中进行的一系列羟醛反应提供了良好的产率(高达 98%)以及高非对映选择性(>99:1)和对映选择性(>99%)。制备的催化剂在反应体系中通过主客体相互作用被聚(AN-MA-β-CD)纳米纤维膜吸附。通过超声波将催化剂从薄膜中分离出来,总回收率为96.2%。该催化剂可重复使用五次,非对映选择性和对映选择性没有显着变化。
Highly modular dipeptide-like organocatalysts for direct asymmetric aldol reactions in brine
作者:Xiao-Mu Hu、Dong-Xu Zhang、Sheng-Yong Zhang、Ping-An Wang
DOI:10.1039/c5ra07019h
日期:——
dipeptide-like organocatalysts derived from proline, amino acids and primaryamines have been prepared for directasymmetricaldolreactions between various aromatic aldehydes and acetone to afford aldol products in good yields (up to 82%) and moderate enantioselectivities (up to 67% ee) with only 1 mol% of catalyst-loading in brine. Under the same conditions, the directasymmetricaldolreactions of aromatic
Highly enantioselective aldol reactions catalyzed by reusable upper rim-functionalized calix[4]arene-based l -proline organocatalyst in aqueous conditions
作者:Zheng-Yi Li、Yuan Chen、Chong-Qian Zheng、Yue Yin、Liang Wang、Xiao-Qiang Sun
DOI:10.1016/j.tet.2016.11.052
日期:2017.1
l-Proline derivatives have been synthesized and employed for the enantioselective aldol reactions between cyclic ketones and aromatic aldehydes in the presence of water. Good to excellent yields (up to 96%), enantioselectivities (up to 99% ee), as well as diastereoselectivities (up to 99:1 dr) were obtained under the optimal reaction conditions. Detailed experiments clearly showed that the hydrophobic
Preparation of prolinamide with adamantane for aldol reaction catalysis in brine and separation using a poly(AN-MA-β-CD) nanofibrous film <i>via</i> host–guest interaction
as organocatalysts in asymmetric aldol reactions. The catalyst with adamantane showed improved catalytic activity, which was further enhanced by using brine as the solvent. A series of aldol reactions in brine at 0 °C provided good yields (up to 98%) with high diastereoselectivities (>99 : 1) and enantioselectivities (>99%). The prepared catalyst was adsorbed by a nanofibrous film of poly(AN-MA-β-CD)
制备了具有双氢电位的脯氨酰胺,并将其用作不对称羟醛反应的有机催化剂。含有金刚烷的催化剂显示出改进的催化活性,通过使用盐水作为溶剂进一步增强了催化活性。在 0 °C 的盐水中进行的一系列羟醛反应提供了良好的产率(高达 98%)以及高非对映选择性(>99:1)和对映选择性(>99%)。制备的催化剂在反应体系中通过主客体相互作用被聚(AN-MA-β-CD)纳米纤维膜吸附。通过超声波将催化剂从薄膜中分离出来,总回收率为96.2%。该催化剂可重复使用五次,非对映选择性和对映选择性没有显着变化。
Highly efficient prolinamide-based organocatalysts for the direct asymmetric aldol reaction in brine
作者:Ya-Ning Jia、Feng-Chun Wu、Xiao Ma、Gong-Jian Zhu、Chao-Shan Da
DOI:10.1016/j.tetlet.2009.04.013
日期:2009.6
Four prolinamide-based organocatalysts were readily synthesized and applied to the directasymmetricaldolreactions of ketones and aromatic aldehydes in brine. When 2,4-dinitrophenol (DNP) was used as an acidic additive, 1 mol % low loading of 2b afforded aldol products with excellent diastereoselectivity of up to 98/2 dr and high enantioselectivity of up to 97% ee.
A class of chiral bifunctional N-prolyl sulfinamide and its TFA salts were prepared and proven to be effective for catalyzing the aldolreaction under solvent-free conditions. In general, the corresponding aldol adducts were obtained with high to excellent yields, and satisfactory diastereo-selectivities and enantioselectivities. A matching effect between chiral proline and sulfinamide moieties was