A known ligand precursor, prepared by an improved method from 1,3-bis(bromomethylbenzene), a base, and (R,R)-2,5-dimethylphospholane-borane, was deprotected with DABCO and used to prepare chiral m-xylene-based PCP pincer complexes. Reaction with Ni(DME)Br₂ and NEt₃ gave square planar Ni(DuPinPhos)(Br) (9), which was crystallographically characterized. Heating with [Ir(COE)₂Cl]₂ yielded the dinuclear hydride complex [Ir(DuPinPhos)(H)(Cl)]₂(μ-C₆H₄(CH₂-dimethylphospholanyl)₂] (10), which contained both pincer chelates and a bridging bis(phospholane). Nickel complex 9 was a catalyst precursor for enantioselective alkylation of secondary phosphines with 2-bromomethylnaphthalene using the base NaOSiMe₃. The dynamic behavior of a catalytic intermediate, the P-stereogenic terminal phosphido complex Ni(DuPinPhos)(PPhIs) (Is = 2,4,6-(i-Pr)₃C₆H₂), was characterized by variable temperature NMR spectroscopy.

中文翻译：

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手性双（磷杂环戊烷）PCP钳配合物：合成，结构和镍催化的不对称膦膦烷基化。

一种已知的配体前体，通过一种改进的方法从1,3-二（溴甲基苯），碱，和（制备- [R ，- [R）-2,5- dimethylphospholane -硼烷，用DABCO脱保护并用于制备手性米二甲苯基于PCP的钳形复合物。与Ni（DME）Br ₂和NEt _3的反应产生方形平面Ni（DuPinPhos）（Br）（9），其在晶体学上表征。与[Ir（COE）₂ Cl] ₂加热，得到双核氢化物配合物[Ir（DuPinPhos）（H）（Cl）] ₂（μ- _C6 H ₄（CH _2-二甲基磷杂环戊基）₂ ]（10），其中既包含钳制螯合物，又包含桥联的双（磷杂环戊烷）。镍络合物9是使用碱NaOSiMe ₃与2-溴甲基萘对仲膦进行对映选择性烷基化的催化剂前体。通过可变温度NMR光谱法表征了催化中间体P-立体生成的末端磷酸络合物Ni（DuPinPhos）（PPhIs）（Is = 2,4,6-（i -Pr）₃ C ₆ H ₂）的动力学行为。。