Isolable f-element diphosphene complexes by phosphinidene group transfer and coupling at uranium.

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Lanthanide and Actinide Chemistry

Background:

• The parent diphosphene (HPPH) molecule is fundamentally important but difficult to study due to its reactivity.
• Existing metal-stabilized HPPH derivatives are scarce, limited by synthetic accessibility.

Purpose of the Study:

• To introduce novel f-element diphosphene (HPPH) complexes.
• To develop new synthetic methodologies for preparing HPPH and related phosphorus motifs using f-elements.
• To investigate the reaction mechanisms and electronic properties of these new complexes.

Main Methods:

• Synthesis of f-element complexes utilizing uranium(III) reagents and 7λ³-phosphadibenzonorbornadiene.
• Computational studies including computed reaction profiles to elucidate reaction pathways.
• Analysis of intermediate radical species and redox-centered behavior.

Main Results:

• Successful construction of parent diphosphene, phosphinidiide, and diphosphorus motifs with f-elements.
• Identification of common initial reaction steps that diverge based on ancillary ligands and substituents.
• Demonstration of a prevalence of open-shell radical intermediates, with P-centered redox chemistry.

Conclusions:

• This work expands the scope of known HPPH complexes to include f-elements.
• The developed synthetic approaches offer new avenues for exploring phosphorus chemistry with f-elements.
• Insights into radical intermediates and P-centered redox activity inform future synthetic strategies.