Efficient stereochemical communication in phosphine-amine palladium-complexes: Exploration of N-substituent effects in coordination chemistry and catalysis
作者:Gergely Farkas、Zsófia Császár、Kristóf Stágel、Evelin Nemes、Szabolcs Balogh、Imre Tóth、Attila Bényei、György Lendvay、József Bakos
DOI:10.1016/j.jorganchem.2017.04.033
日期:2017.10
chelate complexes of type [Pd(1a-e)Cl2] (2a-e) and [Pd(1a-e)(η3-PhCHCHCHPh)]BF4 (3a-e) of a series of systematically varied chiral phosphine-amine ligands (S,S)-Ph2PCH(CH3)CH2CH(CH3)NHR 1a-e (R = benzyl 1a, R = ethyl 1b, R = (S)-α-phenylethyl 1c, R = isopropyl 1d, R = methyl 1e) have been studied. The complexes 2a-e were characterized by X-ray crystallography, DFT analysis and in solution by 1D and 2D NMR
六元型的螯合络合物[钯(1A-E )氯2 ](2A-E )和[钯(1A-E )(η 3 -PhCHCHCHPh)] BF 4(3A-E的一系列系统的)变化手性膦-胺配体(S,S)-Ph 2 PCH(CH 3)CH 2 CH(CH 3)NHR 1a-e(R =苄基1a,R =乙基1b,R =(S)-α-苯乙基1c,R =异丙基1d,R =甲基1e)已被研究。配合物2a-e通过X射线晶体学,DFT分析以及溶液中的1D和2D NMR光谱进行表征。在N-取代基的空间需求和螯合物的变形之间已经观察到非常好的相关性。此外,已经证明,空间上要求更高的N-取代基能够沿着一个单一的,明确定义的构象途径在更大程度上扭曲螯合物。因此,N取代基的仔细变化可以对金属的配位球进行精确的立体化学微调。作为该概念的证据,对配合物3a-e的研究表明,exo / endo通过适当地选择氮取代基,可以容易地改变烯丙基的比例以及