SusChEM: IUPAC: Harnessing the Unquenched Reactivity of Novel Frustrated Lewis Pairs for Transition Metal-Free Hydrogenation Catalysis

在这个由化学系化学催化计划资助的项目中，德克萨斯理工大学的克莱门斯·克雷姆普纳教授研究了受挫Lewis对(FLP)作为昂贵、丰度较低和有毒的贵金属的替代品的使用，这些贵金属用于不饱和有机物种的催化加氢。由于不能形成经典的Lewis酸碱络合物，FLP是空间阻碍的Lewis酸碱对，具有未熄灭的反应性。通过计算/实验相结合的方法，确定了能够可逆地裂解二氢的Lewis酸和碱的新组合。有吸引力的弱Lewis酸包括硼酸酯和硼酸酯，因为这些化合物很容易用廉价的原料合成或以低成本在商业上获得。使用磷腈和胍类作为碱组分。通过模块化的FLP合成、详细的催化测试和对新型催化剂及其潜在催化机理的计算研究相结合，扩大了催化剂开发的进展。该项目是与南京大学的李淑华教授(南京大学，中国)和德国亚琛RWTH的尤尔根·克兰克梅尔教授合作完成的。这三个小组将各自的专业领域结合在一起，生产亚胺、酮和烯烃的无过渡金属氢化反应，这些都是制药业的重要底物。这项工作的更广泛影响包括对博士后研究员、研究生和本科生的领导能力培训，以及国际间的思想和专门知识交流。

In this project, funded by the Chemical Catalysis Program of the Chemistry Division, Professor Clemens Krempner of Texas Tech University examines the use of frustrated Lewis pairs (FLPs) as replacements for expensive, less abundant, and toxic precious metals used in the catalytic hydrogenation of unsaturated organic species. FLPs are sterically-encumbered Lewis acid-base pairs of unquenched reactivity due to their inability to form classical Lewis-acid-base complexes. Novel combinations of Lewis acids and bases, capable of reversibly cleaving dihydrogen, are identified by a combined computational / experimental approach. Attractive weak Lewis acids include boronic and boric esters, as these compounds are readily synthesized from inexpensive starting materials or are commercially available at low cost. Phosphazenes and guanidines are used as the base components. Progress in catalyst development is amplified by the combination of modular FLP synthesis, detailed catalytic testing, and computational investigations on novel catalysts and the underlying catalytic mechanisms. This project is performed in collaboration with Professor Shuhua Li (Nanjing University, Nanjing, China) and Professor Juergen Klankermayer (RWTH Aachen, Aachen, Germany). Together, these three groups combine their separate areas of expertise to produce transition metal-free hydrogenation of imines, ketones and olefins - important substrates in the pharmaceutical industry. The broader impacts of this work include leadership training for postdoctoral fellows and graduate and undergraduate students and an international exchange of ideas and expertise.