合成和表征与2,6-bis(pyrazol-3-yl) pyridine (bpp) 连接体支持的七度协调 ((II) 复合体
Arno Estival1, Luis E Blancarte2, Loïc Pinto1
1LCC-CNRS, Université de Toulouse, CNRS, UPS, 205 route de Narbonne, BP44099 F-31077 Toulouse cedex 4, France. antoine.simonneau@lcc-toulouse.fr.
Dalton transactions (Cambridge, England : 2003)
|January 10, 2025
概括
研究人员通过使用功能接器连接体,2,6-bis(pyrazol-3-yl) pyridine (bpp) 合成了新型(II) 复合体,由于金属连接体合作性和氧化还原非无罪性,它们在催化过程中表现有前途.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 协调化学 协调化学
背景情况:
- 功能性器配体,特别是2,6-bis(pyrazol-3-yl) pyridine (bpp) 配体,由于金属配体合作性和氧化还原非无罪性,在催化过程中至关重要.
- 含有这些连接体的复合物对开发新的催化系统有兴趣.
研究的目的:
- 为了合成和描述由功能化的bpp联结体支持的新型七度协调 (((II) 复合体.
- 为了探索 2,6-bis(5-trifluoromethylpyrazol-3-yl) pyridine (LCF3) 和 2,6-bis(5-tert-butylpyrazol-3-yl) pyridine (LtBu) 连接体与的协调化学反应.
- 为了研究这些新的复合物的特性和反应性.
主要方法:
- (0) 前体与 LCF3 和 LtBu 连接体在和碳连接体的存在下发生反应.
- 氧化合成使用银酸或银氧化物来提高产量.
- 使用NMR,IR,UV-Vis光谱,单晶X射线衍射 (sc-XRD) 和循环/正方波电压测量进行了表征.
- 对去质子化的配体进行再质子化研究.
主要成果:
- 合成七度协调的Mo(II) 复合物[Mo(CO) 2 ((bpp) ((PMe3-nPPhn) ] (4a-c和5a-c) 含有双重脱质 bpp 配体,尽管最初的产量很低.
- 通过氧化合成途径实现了复合物4a-c和5a-c的提高产量.
- 鉴定证实了合成复合物的结构和电子特性.
- 在5a-c复合体中对LtBu联体的重新质子化产生了双离子 (((II) 复合体[Mo (((CO)) 2 (((LtBu)) ((PMe3-nPPhn) 2)) [OTf] 2 (6a-c).
- 对LCF3支持的复合物 (4a-c) 进行酸性处理,导致分解.
结论:
- 成功合成和特征化了具有功能化的bpp配体的新型七度协调(II) 复合物.
- 氧化条件显著提高了这些目标复合物的产量.
- LtBu接体可以很容易地重新质子化,提供进一步的合成可能性,而LCF3接体在酸性条件下不太稳定.
- 这些发现有助于开发具有潜在催化应用的新有机金属复合物.
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