Finding Furfural Hydrogenation Catalysts via Predictive Modelling
作者:Zea Strassberger、Maurice Mooijman、Eelco Ruijter、Albert H. Alberts、Ana G. Maldonado、Romano V. A. Orru、Gadi Rothenberg
DOI:10.1002/adsc.201000308
日期:2010.9.10
studies showed that this transfer hydrogenation follows the so‐called monohydride pathway. Using these data, we built a predictivemodel for 13 of the catalysts, based on 2D and 3D molecular descriptors. We tested and validated the model using the remaining five catalysts (cross‐validation, R2=0.913). Then, with this model, the conversion and selectivity were predicted for four completely new ruthenium‐carbene
我们结合多组分反应、催化性能研究和预测模型来寻找转移氢化催化剂。最初合成并筛选了 18 种钌卡宾配合物,并在糠醛与异丙醇配合物的转移氢化反应中筛选出不同的产率,从 62% 到 >99.9%,没有明显的结构/活性相关性。对照实验证明,卡宾配体在整个反应过程中始终与钌中心保持配位。氘标记研究显示出次级同位素效应(k H : k D = 1.5)。进一步的机理研究表明,这种转移氢化遵循所谓的一氢化物途径。利用这些数据,我们基于 2D 和 3D 分子描述符建立了 13 种催化剂的预测模型。我们使用其余五种催化剂测试并验证了模型(交叉验证,R 2 =0.913)。然后,利用该模型,预测了四种全新的钌卡宾配合物的转化率和选择性。然后合成并测试这四种催化剂。结果与模型预测的误差在 3% 以内,证明了预测模型在催化剂优化中的有效性和价值。
Scope and Limitations of an Efficient Four-Component Reaction for Dihydropyridin-2-ones
作者:Rachel Scheffelaar、Monica Paravidino、Anass Znabet、Rob F. Schmitz、Frans J. J. de Kanter、Martin Lutz、Anthony L. Spek、Célia Fonseca Guerra、F. Matthias Bickelhaupt、Marinus B. Groen、Eelco Ruijter、Romano V. A. Orru
DOI:10.1021/jo902613j
日期:2010.3.5
4-dihydropyridin-2-ones could be prepared using a four-componentreaction between phosphonates, nitriles, aldehydes, and isocyanoacetates. The reaction involves initial formation of a 1-azadiene intermediate which is trapped in situ by an isocyanoacetate to give the desired heterocyclic scaffold through cyclocondensation. The full scope and limitations of this four-componentreaction are described. Variation of the
Asymmetric Formal [3+2] Cycloaddition Reaction of Isocyanoesters to 2‐Oxobutenoate Esters by a Multifunctional Chiral Silver Catalyst
作者:Jin Song、Chang Guo、Peng‐Hao Chen、Jie Yu、Shi‐Wei Luo、Liu‐Zhu Gong
DOI:10.1002/chem.201100636
日期:2011.7.4
Silver‐standard selectivity! The first highly enantioselective formal [3+2] cycloaddition reaction of isocyanoesters with 2‐oxobutenoate esters catalyzed by a chiralsilver complex proceeded readily under the catalysis of a multifunctional chiralsilver complex in high yields and enantiometric excess (ee) values of up to 98 % (see scheme).
Chiral squaramides catalyzed diastereo- and enantioselective Michael addition of α-substituted isocyanoacetates to N-aryl maleimides
作者:Mei-Xin Zhao、Fei-Hu Ji、Deng-Ke Wei、Min Shi
DOI:10.1016/j.tet.2013.09.084
日期:2013.12
An efficient diastereo- and enantioselective Michael addition of α-substituted isocyanoacetates to N-aryl maleimidescatalyzed by quinine or cyclohexane-1,2-diamine derived squaramide catalysts has been disclosed, affording the corresponding adducts in good yields (up to 99%), high diastereoselectivities (up to >20:1 dr) and good to excellent enantioselectivities (up to 94% ee) under mild conditions
Cinchona alkaloid thiourea mediated asymmetric Mannich reaction of isocyanoacetates with isatin-derived ketimines and subsequent cyclization: enantioselective synthesis of spirooxindole imidazolines
作者:Mei-Xin Zhao、Lei Jing、Hao Zhou、Min Shi
DOI:10.1039/c5ra17075c
日期:——
The organocatalyzed asymmetric Mannich reaction of isocyanoacetates with isatin ketimines and subsequent cyclization were developed, leading to spirooxindole imidazolines in high yields and excellent stereoselectivities.