Newman-Stonebraker Samuel H, Raab T Judah, Roshandel Hootan, Doyle Abigail G
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States.
J Am Chem Soc. 2023 Sep 6;145(35):19368-19377. doi: 10.1021/jacs.3c06233. Epub 2023 Aug 23.
Nickel's +1 oxidation state has received much interest due to its varied and often enigmatic behavior in increasingly popular catalytic methods. In part, the lack of understanding about Ni results from common synthetic strategies limiting the breadth of complexes that are accessible for mechanistic study and catalyst design. We report an oxidative approach using tribromide salts that allows for the generation of a well-defined precursor, [Ni(COD)Br], as well as several new Ni complexes. Included among them are complexes bearing bulky monophosphines, for which structure-speciation relationships are established and catalytic reactivity in a Suzuki-Miyaura coupling (SMC) is investigated. Notably, these routes also allow for the synthesis of well-defined monomeric bpy-bound Ni complexes, which has not previously been achieved. These complexes, which react with aryl halides, can enable previously challenging mechanistic investigations and present new opportunities for catalysis and synthesis.
镍的 +1 氧化态因其在日益流行的催化方法中表现出的多样且常常神秘的行为而备受关注。部分原因在于，对镍缺乏了解是由于常见的合成策略限制了可用于机理研究和催化剂设计的配合物的范围。我们报道了一种使用三溴化物盐的氧化方法，该方法能够生成一种明确的前体 [Ni(COD)Br] 以及几种新的镍配合物。其中包括带有庞大单膦配体的配合物，我们建立了其结构 - 形态关系，并研究了它们在铃木 - 宫浦偶联反应（SMC）中的催化反应活性。值得注意的是，这些路线还能够合成明确的单体联吡啶配位的镍配合物，这在以前是无法实现的。这些与芳基卤化物反应的配合物能够开展之前具有挑战性的机理研究，并为催化和合成提供新的机会。
