Double dative bond between divalent carbon(0) and uranium.

Area of Science:

• Organometallic Chemistry
• f-Block Element Chemistry
• Coordination Chemistry

Background:

• Dative bonds are common between p- and d-block elements.
• Species with double dative bonds, donating two electron pairs to one acceptor, are exceptionally rare.
• Understanding bonding in f-block element complexes is crucial for advancing inorganic chemistry.

Purpose of the Study:

• To synthesize and characterize novel complexes of uranium tetrachloride (UCl4) with carbodiphosphoranes (CDP).
• To investigate the presence and nature of double dative bonds in f-block element chemistry.
• To explore the potential for creating new f-block compounds with double dative bonds.

Main Methods:

• Synthesis of uranium complexes using UCl4 and carbodiphosphoranes.
• Single-crystal X-ray diffraction to determine molecular structure and bond lengths.
• Bonding analysis to elucidate the electronic structure and nature of the U-C interaction.

Main Results:

• Successful synthesis of UCl4-CDP complexes featuring formal double dative bonds (Cl4U⇇CDP).
• X-ray diffraction revealed uranium-carbon bond distances consistent with double bond character.
• Bonding analysis indicated uranium-carbone complexes with divalent carbon(0) ligands, not uranium-carbene species.

Conclusions:

• The study reports rare examples of double dative bonds involving f-block elements.
• Introduces the concept of double dative bonds between carbones and f-block elements.
• Paves the way for constructing new complexes with double dative bonds, expanding f-block chemistry applications.