Scholarlink

<p>Sustainable catalysts based on main-group elements, such as frustrated Lewis pairs (FLPs), have emerged as alternatives to precious metal systems. The initial reaction of the Lewis acid, Lewis base and small molecule (<i>e.g</i>. H<sub>2</sub>) is formally termolecular, but the reaction is rationalised by the pre-association of the acid and base in an encounter complex. Here we show that the charge-transfer band between P(mes)<sub>3</sub> and B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub> can be analysed by supramolecular UV-vis spectroscopic techniques to provide the key thermodynamic parameter, the association constant (<i>K</i><sub>a</sub>), for the active encounter complex, <i>i.e</i>. the pre-associated complex that is specifically in the correct orientation for small-molecule activation. We also demonstrate that a higher concentration of active encounter complex in solution leads to a faster activation of hydrogen. This method enables researchers to directly probe the complex that underpins FLP small-molecule activation and subsequent catalysis, and will aid the design of more active sustainable catalysts.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Quantifying interactions in the active encounter complex of frustrated Lewis pairs

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年4月17日

查看全文
  • Alastair T. Littlewood,
  • Tao Liu,
  • Laura E. English,
  • Linjiang Chen,
  • Timothy A. Barendt,
  • Andrew R. Jupp

摘要

Sustainable catalysts based on main-group elements, such as frustrated Lewis pairs (FLPs), have emerged as alternatives to precious metal systems. The initial reaction of the Lewis acid, Lewis base and small molecule (e.g. H2) is formally termolecular, but the reaction is rationalised by the pre-association of the acid and base in an encounter complex. Here we show that the charge-transfer band between P(mes)3 and B(C6F5)3 can be analysed by supramolecular UV-vis spectroscopic techniques to provide the key thermodynamic parameter, the association constant (Ka), for the active encounter complex, i.e. the pre-associated complex that is specifically in the correct orientation for small-molecule activation. We also demonstrate that a higher concentration of active encounter complex in solution leads to a faster activation of hydrogen. This method enables researchers to directly probe the complex that underpins FLP small-molecule activation and subsequent catalysis, and will aid the design of more active sustainable catalysts.