A crystalline stannyne

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Synthetic Chemistry

Background:

• Synthesis of heavier group 14 element alkyne analogues (E = Si, Ge, Sn, Pb) is challenging.
• Neutral silynes and germynes are stable only at low temperatures with Lewis base stabilization.

Purpose of the Study:

• To synthesize and characterize a base-free stannyne at room temperature.
• To investigate the electronic structure and reactivity of the novel carbon-tin multiple bond.

Main Methods:

• Strategic use of bulky cyclic phosphino and terphenyl ligands.
• Isolation and structural characterization of the stannyne at room temperature.
• Reactivity studies with isocyanides, dienes, and other reagents.

Main Results:

• Isolation of a base-free stannyne (R¹-C≡Sn-R²) at room temperature.
• Characterization of an allenic structure with delocalized π-electrons and a C-Sn multiple bond with ionic character.
• Demonstrated reactivity analogous to carbenes and stannylenes.

Conclusions:

• The developed synthetic strategy enables the isolation of stable stannynes.
• The stannyne exhibits unique electronic properties and reactivity, expanding the scope of group 14 chemistry.
• This work provides a foundation for exploring heavier alkyne analogues.