<i>E</i>-Selective Synthesis and Coordination Chemistry of Pyridine-Phosphaalkenes: Five Ligands Produce Four Distinct Types of Ru(II) Complexes
作者:Mika L. Nakashige、Jarin I. P. Loristo、Lesley S. Wong、Joshua R. Gurr、Timothy J. O’Donnell、Wesley Y. Yoshida、Arnold L. Rheingold、Russell P. Hughes、Matthew F. Cain
DOI:10.1021/acs.organomet.9b00425
日期:2019.9.9
spatial arrangement of donors to Ru(II) with an agostic Ru–H–C interaction serving as the sixth donor to the transition metal center. Ligands 2b,d,e and Ru(II) complexes 3b, 4b,e and 5a were all characterized by X-ray crystallography. Six-coordinate 6c featured a structure similar to 4b,d,e, but with the CF3 substituent acting as a weakly bound sixth ligand to the Ru(II) center, as observed by 31P1H}
吡啶-磷烯烃(PN)配体2a – e使用磷-维蒂希方法以E选择性方式制备。用RuCl 2(PPh 3)3处理这五个配体(仅在其6取代基中发生变化),产生了四种不同类型的配位配合物:吡啶-磷烯烃衍生的3b,d,环化的4e以及六配位的5a和6c。长时间在THF中加热3b,d导致Mes *基团的C–H活化和环化生成4b,d具有与金属中心结合的二齿吡啶-膦烷配体。配合物5a,也具有新形成的磷环,包含Ru(II)供体的不同空间排列,Ru-H-C相互作用很强,是过渡金属中心的第六个供体。配体2b,d,e和Ru(II)配合物3b,4b,e和5a均通过X射线晶体学表征。六坐标6c具有类似于4b,d,e的结构,但具有CF 3如31 P 1 H}和19 F NMR光谱所观察到的,该取代基充当与Ru(II)中心的弱结合第六配体。计算得出的6c结构确定最接近的Ru---F接触为2.978Å。