Nickel-Catalyzed Enantioselective Reductive Cross-Coupling of Styrenyl Aziridines
作者:Brian P. Woods、Manuel Orlandi、Chung-Yang Huang、Matthew S. Sigman、Abigail G. Doyle
DOI:10.1021/jacs.7b03448
日期:2017.4.26
to asymmetric catalysis using a chiral bioxazolineligand for Ni. The process allows facile access to highly enantioenriched 2-arylphenethylamines from racemic aziridines. Multivariate analysis revealed that ligand polarizability, among other features, influences the observed enantioselectivity, shedding light on the success of this emerging ligand class for enantioselective Ni catalysis.
报道了一种 Ni 催化的苯乙烯基氮丙啶与芳基碘化物的还原交叉偶联。该反应通过立体会聚机制进行,因此适用于使用 Ni 的手性生物恶唑啉配体进行不对称催化。该过程允许从外消旋氮丙啶轻松获得高度对映体富集的 2-芳基苯乙胺。多变量分析表明,配体极化率等特征会影响观察到的对映选择性,揭示了这种新兴配体类别在对映选择性 Ni 催化方面的成功。
Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics
propargylic position resemble the sidechain present at the Cα of amino acids. Whereas propargylamines with (cyclo)alkyl substituents can be prepared in a direct manner, residues with polar functional groups require suitable protective groups. The presence of particular functional groups in the sidechain in some cases leads to remarkable side reactions of the alkyne moiety. Thus, electron-withdrawing substituents
Asymmetric Synthesis of Protected 1,2-Amino Alcohols Using <i>tert</i>-Butanesulfinyl Aldimines and Ketimines
作者:Tony P. Tang、Steven K. Volkman、Jonathan A. Ellman
DOI:10.1021/jo0156868
日期:2001.12.1
tert-Butanesulfinyl aldimines and ketimines bearing an alpha-benzyloxy or alpha-silyloxy substituent serve as precursors in the synthesis of protected 1,2-amino alcohols in high yields and diastereoselectivities. General protocols are described for the addition of unbranched alkyl, branched alkyl, and aryl organometallic reagents to N-sulfinyl aldimines 1 and 2 and ketimines 5 and 6. Furthermore, the
AsymmetricvinylogousMannichreaction (VMR) of 2-(tert-butyldimethylsilyloxy)furan (TBSOF, 1) with (RS)- or (SS)-t-BS-imines (3) furnished 5-aminoalkylbutenolides 7a–k in 75–87% yields with anti/syn ratios ranging from 75:25 to 97:3. Butenolides 7a–f,k were readily converted into substituted lactones 8 and 5 and 6-substituted 5-hydroxypiperidin-2-ones 11a–g, which are, in turn, key intermediates for