3.02 | Hydrides and Olefins

April 13th 2022 | In this lecture we discussed the properties of dihydrogen, hydride, and olefinic ligands. The differences between a dihydrogen and hydride ligand where explained and how they can be converted to one another via oxidative addition and reductive elimination, where pi-backbonding plays a crucial role. We also discussed how metal-hydrides could be generated and we looked at there overall reactivity by analyzing their HOMO and their LUMO.

Surprisingly, for olefinic ligands, a similar picture emerged where pi-backbond results in two extremes when an olefin binds to the metal center (i.e. a metal-alkene complex vs. a metallocyclopropane). The theoretical explanation was provided by the Dewar-Chart-Duncanson Model. We also analyzed the HOMO/LUMO of ethylene, butadiene, and cyclopentadienide, and with what orbitals they could overlap with a prospective metal center.

The video to the lecture can be found below.