Probing Electronic Effects in the Asymmetric Heck Reaction with the BIPI Ligands
作者:Carl A. Busacca、Danja Grossbach、Regina C. So、Erin M. O'Brie、Earl M. Spinelli
DOI:10.1021/ol0340179
日期:2003.2.1
new BIPI ligands are phosphinoimidazolines that can be electronically tuned in three different ligand regions to explore electronic effects in asymmetric catalysis. Their application to the asymmetricHeckreaction (AHR) in the creation of a chiral quaternary center is described. Enantioselectivity is shown for the first time to depend linearly on phosphine electron density. Changing the ligand basicity
for the preparation of enantiomericallyenriched C 2 -symmetrical vicinal diamines via the addition of organometallic reagents to a chiral bisimine, which gives access to a variety of optically pure aromatic and aliphatic C 2 -symmetrical vicinal diamines in high yields. The 'Cram-Davis' open transition state model is proposed to rationalize the observed stereoselectivities for the addition of organolithium
通过将有机金属试剂添加到手性双亚胺中,开发了一种有效且直接的制备对映体富集的 C 2 对称邻二胺的方法,该方法可以获得各种光学纯的芳香族和脂肪族 C 2 对称邻二胺高产量。提出了“Cram-Davis”开放过渡态模型,以合理化观察到的将有机锂试剂添加到双亚胺中的立体选择性。
Convenient routes to symmetrical benzils and chiral 1,2-diaryl-1,2-diaminoethanes, useful controllers and probes for enantioselective synthesis
作者:E.J. Corey、Duck-Hyung Lee、Sepehr Sarshar
DOI:10.1016/0957-4166(94)00336-a
日期:1995.1
Pathways for the diastereoselective preparation of chiral 1,2-diaryl-1,2-diaminoethanes from ArCOOH, ArCHO or ArBr are described.
Synthesis and in vitro antitumor activity of novel iridium(III) complexes with enantiopure C2-symmetrical vicinal diamine ligands
作者:Qing Yang、Jun Chang、Jiao Song、Meng-Ting Qian、Jian-Ming Yu、Xun Sun
DOI:10.1016/j.bmcl.2013.06.024
日期:2013.8
Four novel iridium(III) complexes with enantiopure C2-symmetrical vicinal diamineligands were designed, synthesized, and characterized by FT-IR, NMR, and MS. The cytotoxicities of all of the complexes against the human solid tumor cell lines A2780, A549, KB, and MDA-MB-231 were evaluated. Both R,R-configured complexes (R,R)-5a and (R,R)-5b exhibited more potent or similar activity compared with oxaliplatin