Singlet (Phosphino)phosphinidenes are Electrophilic

Area of Science:

• Organophosphorus Chemistry
• Main Group Chemistry
• Reaction Mechanisms

Background:

• Phosphinidenes are highly reactive phosphorus species.
• Understanding their electronic structure and reactivity is crucial for synthetic applications.
• Room-temperature stable phosphinidenes offer new avenues for studying these elusive intermediates.

Purpose of the Study:

• To investigate the reactivity of room-temperature stable (phosphino)-phosphinidenes.
• To determine the electronic nature and electrophilicity of these phosphinidene species.
• To elucidate the reaction pathways with various unsaturated compounds.

Main Methods:

• Reactions with carbon monoxide, singlet carbenes (e.g., imidazol-2-ylidene), and phosphines.
• Electronic ground-state calculations.
• Fukui function calculations.
• Competition experiments.

Main Results:

• Formation of phosphaketene, phosphinidene-carbene, and phosphinidene-phosphine adducts.
• Observed electrophilic reactivity of (phosphino)-phosphinidenes.
• Competition experiments and Fukui function calculations support electrophilic character.

Conclusions:

• Room-temperature stable (phosphino)-phosphinidenes exhibit electrophilic behavior.
• This electrophilicity is consistent with their electron-deficient nature.
• The study clarifies the reactivity patterns of these important phosphorus intermediates.