Syntheses, structures, and reactivity of early transition metal complexes bearing a phosphide-donor multidentate ligand

建立了含磷化氢链链的环戊二烯ER′_3C_5H_4CH_2CH_2P(R)Mes （ER′_<3 >= SiMe_3, SnBu_3; R = SiMe_3 H; Mes = 2,4,6-三甲基苯基）及其Li盐的合成方法。考察了Cp衍生物与mc_4 （M = Zr, Hf）的反应。当R = SiMe_3时，形成{C_5H_4CH_2CH_2P(SiMe_3)Mes}MCl_3，磷化氢部分不与中心金属配位。当R = H时，复杂反应发生。相反，当MCl_4(tht)^2作为起始配合物（代表四氢噻吩）时，{C_5H_4CH_2CH_2P(H)Mes}MCl_3（tht）是由膦与中心金属配位形成的。研究了这些磷化氢配合物转化为磷化物的过程。三氯化物配合物没有转化成相应的磷化物配合物。接着，进行了Cl/烷基交换反应。当R = H时，与Mg(CH_2Ph)_2(thf)_2反应生成三苄基络合物。虽然磷化氢部分不与中心金属配位，但该配合物在甲苯中的热裂解导致形成二苄基磷化物并释放甲苯。三氯配合物与烯丙基格氏试剂在醚中反应生成棕色粉末的二烯丙基磷化物配合物。考察了分离得到的磷悬垂配合物的反应性。与大体积醇2,6-二叔丁基苯酚（HOR）的反应表明，O-H键加成于M- p键得到膦-非配位芳基配合物{C_5H_4CH_2CH_2P(H)Mes}M(C_3H_5)_2 (OR)，随后丙烯消去得到膦-配位配合物{C_5H_4CH_2CH_2PMes}M(C_3H_5)（OR）。

Synthetic methods of cyclopentadienes with a phosphine pendant, ER'_3C_5H_4CH_2CH_2P(R)Mes (ER'_<3 >= SiMe_3, SnBu_3; R = SiMe_3 H; Mes = 2,4,6-trimethylphenyl) and their Li salts were developed. The reactions of the Cp derivatives with MCl_4 (M = Zr, Hf) were examined. It was found that when R = SiMe_3, {C_5H_4CH_2CH_2P(SiMe_3)Mes}MCl_3 is formed and the phosphine portion does not coordinate to the central metal. When R = H, the complicated reactions tool place. In contrast, when MCl_4(tht)^2 was used as a starting complex where tht stands for tetrahydrothiophene, {C_5H_4CH_2CH_2P(H)Mes}MCl_3(tht) was formed with coordination of the phosphine to the central metal.The conversion of these phosphine complexes into the phosphide complexes was examined. The trichloride complexes were not converted into the corresponding phosphide complexes. Next, a Cl/alkyl exchange reaction was attempted. In the case of R = H, a tribenzyl complex was formed in the reaction with Mg(CH_2Ph)_2(thf)_2. Although the phosphine part does not coordinate to the central metal the thermolysis of this complex in toluene led to the formation of a dibenzylphosphide complex with releasing toluene. The reaction of the trichloride complex with an allyl Grignard reagent in ether yielded a diallylphosphide complex as a brown powder.The reactivity of the isolated phosphide-pendant complex was examined. The reaction with bulky alcohol, 2,6-ditertiaryBu-phenol (HOR), revealed that the O-H bond addition to the M-P bond takes place to give a phosphine-uncoordinated aryloxy complex {C_5H_4CH_2CH_2P(H)Mes}M(C_3H_5)_2 (OR), followed by the elimination of propene to give a phosphide-coordinated complex {C_5H_4CH_2CH_2PMes}M(C_3H_5)(OR).