Enantioselective Intermolecular Addition of Aliphatic Amines to Acyclic Dienes with a Pd–PHOX Catalyst
作者:Nathan J. Adamson、Ethan Hull、Steven J. Malcolmson
DOI:10.1021/jacs.7b03480
日期:2017.5.31
We report a method for the catalytic, enantioselective intermolecular addition of aliphatic amines to acyclic 1,3-dienes. In most cases, reactions proceed efficiently at or below room temperature in the presence of 5 mol % of a Pd catalyst bearing a PHOX ligand, generating allylic amines in up to 97:3 er. The presence of an electron-deficient phosphine within the ligand not only leads to a more active
Formamides derived from N-methyl amino acids serve as new chiral organocatalysts in the enantioselective reduction of aromatic ketimines with trichlorosilane
作者:Andrei V. Malkov、Sigitas Stončius、Kenneth N. MacDougall、Andrea Mariani、Grant D. McGeoch、Pavel Kočovský
DOI:10.1016/j.tet.2005.08.117
日期:2006.1
Asymmetric reduction of N-aryl ketimines 1a–k, 43, and 45 with trichlorosilane can be catalyzed by new N-methyl l-amino acid-derived Lewis-basic organocatalysts, such as the valine-derived bisamide 3d (10 mol%), in toluene at room temperature with high enantioselectivity (≤92% ee). The structure–reactivity investigation shows that the product configuration is controlled by the nature of the side chain
N-芳基酮亚胺1a - k,43和45用三氯硅烷的不对称还原可以由新的N-甲基l-氨基酸衍生的Lewis碱性有机催化剂催化,例如缬氨酸衍生的双酰胺3d(10 mol%),在室温下在甲苯中具有高对映选择性(≤92%ee)。结构反应研究表明,产物构型受催化剂支架侧链性质的控制(例如,在3d和6e中,i -Pr vs Me)),因此相同绝对构型的催化剂可能会诱导产物相反的对映异构体的形成。催化剂与传入的亚胺之间的芳烃-芳烃相互作用似乎是不对称诱导的前提。这种无金属的有机催化方案与传统的金属催化方法相比具有竞争优势。
A Highly Enantioselective Lewis Basic Organocatalyst for Reduction of <i>N</i>-Aryl Imines with Unprecedented Substrate Spectrum
作者:Zhouyu Wang、Xiaoxia Ye、Siyu Wei、Pengcheng Wu、Anjiang Zhang、Jian Sun
DOI:10.1021/ol060112g
日期:2006.3.2
L-Pipecolinic acid derived formamides have been developed as highly efficient and enantioselective Lewis basic organocatalysts for the reduction of N-aryl imines with trichlorosilane. Catalyst 4b afforded high isolated yields (up to 98%) and enantioselectivities (up to 96%) under mild conditions with an unprecedented substrate spectrum.
Enantioselective, Stereodivergent Hydroazidation and Hydroamination of Allenes Catalyzed by Acyclic Diaminocarbene (ADC) Gold(I) Complexes
作者:Dimitri A. Khrakovsky、Chuanzhou Tao、Miles W. Johnson、Richard T. Thornbury、Sophia L. Shevick、F. Dean Toste
DOI:10.1002/anie.201601550
日期:2016.5.10
The gold‐catalyzed enantioselective hydroazidation and hydroamination reactions of allenes are presented herein. ADC gold(I) catalysts derived from BINAM were critical for achieving high levels of enantioselectivity in both transformations. The sense of enantioinduction is reversed for the two different nucleophiles, allowing access to both enantiomers of the corresponding allylic amines using the
Cooperative Catalysis by Palladium and a Chiral Phosphoric Acid: Enantioselective Amination of Racemic Allylic Alcohols
作者:Debasis Banerjee、Kathrin Junge、Matthias Beller
DOI:10.1002/anie.201405511
日期:2014.11.24
Cooperativecatalysis by [Pd(dba)2] and the chiralphosphoricacid BA1 in combination with the phosphoramidite ligand L8 enabled the efficient enantioselectiveamination of racemicallylicalcohols with a variety of functionalized amines. This catalytic protocol is highly regio‐ and stereoselective (up to e.r. 96:4) and furnishes valuable chiral amines in almost quantitative yield.