[5] After his PhD, he was a postdoctoral researcher with Hugh Felkin at the Institut de Chimie des Substances Naturelles at Gif-sur-Yvette, near Paris.

[10] This catalyst, utilizing iridium as the active metal, displays exceptional efficiency, regio- and stereoselectivity in hydrogenation reactions.

Surprisingly, Crabtree also observed Y–H σ bonds (Y= B or metal) acting as acceptors, leading to X–H···H–Y structures with significantly shorter H···H distances compared to typical contacts.

Unlike C2 coordinated imidazolylidenes, mesoionic carbenes possess only charge-separated electronic resonance structures, allowing for greater adaptability to metal centers within catalytic cycles.

Crabtree has developed novel methods for generating and isolating abnormal carbenes, providing insights into their structures and stability under different conditions.

[16] Crabtree's research has made significant advancements in our understanding of O–O bond formation within manganese di-μ-oxo dimers involved in oxygen evolution.

His approach entails selecting unique projects, conducting early critical experiments, transitioning between problems, developing air-stable catalysts, and educating through his writing.