Selikhov Alexander N, Plankin Gleb S, Cherkasov Anton V, Shavyrin Andrey S, Louyriac Elisa, Maron Laurent, Trifonov Alexander A
G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences , 49 Tropinina str. , 603137 , Nizhny Novgorod , GSP-445, Russia.
A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences , 28 Vavilova str. , 119991 , Moscow , GSP-1, Russia.
Inorg Chem. 2019 Apr 15;58(8):5325-5334. doi: 10.1021/acs.inorgchem.9b00490. Epub 2019 Apr 1.
A series of Ln(II) and Ca(II) bis(alkyl) complexes with bulky benzhydryl ligands, [( p- tBu-CH)CH]M(L ) (M = Sm, L = DME, n = 2 (1); M = Sm, Yb, Ca, L = TMEDA, n = 1 (2, 3, 4), were synthesized by the salt-metathesis reaction of MI(THF) ( n = 0-2) and [( p- tBu-CH)CH]Na. In complex 1, the benzhydryl ligands are bound to the metal center in η-coordination mode. Unlike complex 1, in isomorphous complexes 3 and 4, due to the coordination unsaturation of the metal center, the both benzhydryl ligands coordinate to the metal in η-fashion. In complex 2, one ligand is η-coordinated while the second one is η-coordinated to the Sm(II) ion. Complexes 2-4 demonstrated unprecedented thermal stability: no evidence of decomposition was observed after heating their solutions in CD at 100 °C during 72 h. Complex 1 behaves differently: thermolysis in CD solution at 75 °C results in total decomposition in 8 h. Addition of DME promotes decomposition of 2-4 and makes it feasible at 40 °C. Complexes 1-4 demonstrated high catalytic activity and excellent regio- and chemoselectivities in intermolecular hydrophosphination of double and triple C-C bonds with both primary and secondary phosphines. Complexes 2 and 3 enable addition of PhPH toward the internal C═C bond of Z- and E-stilbenes with 100% conversion under mild conditions. Double sequential hydrophosphination of phenylacetylene with PhPH and PhPH was realized due to the application of Yb(II) complex as a catalyst.
一系列带有庞大二苯甲基配体的Ln(II)和Ca(II)双(烷基)配合物，[(p - tBu - CH)CH]M(L )（M = Sm，L = DME，n = 2 (1)；M = Sm、Yb、Ca，L = TMEDA，n = 1 (2、3、4)），通过MI(THF) （n = 0 - 2）与[(p - tBu - CH)CH]Na的盐复分解反应合成。在配合物1中，二苯甲基配体以η配位模式与金属中心结合。与配合物1不同，在同构的配合物3和4中，由于金属中心的配位不饱和，两个二苯甲基配体均以η方式与金属配位。在配合物2中，一个配体是η配位，而另一个是与Sm(II)离子以η配位。配合物2 - 4表现出前所未有的热稳定性：在100℃下将它们在CD中的溶液加热72小时后，未观察到分解迹象。配合物1的行为不同：在75℃下于CD溶液中进行热解，8小时内完全分解。加入DME会促进2 - 4的分解，并使其在40℃下可行。配合物1 - 4在分子间双、三C - C键与伯膦和仲膦的氢膦化反应中表现出高催化活性以及优异的区域和化学选择性。配合物2和3能够在温和条件下使PhPH加成到Z - 和E - 二苯乙烯的内C═C键上，转化率达100%。由于使用Yb(II)配合物作为催化剂，实现了苯乙炔与PhPH和PhPH的双连续氢膦化反应。
