Designing Stability into Thermally Reactive Plumbylenes

Area of Science:

• Organometallic Chemistry
• Materials Science
• Coordination Chemistry

Background:

• Lead analogues of N-heterocyclic carbenes (NHPbs) are poorly understood.
• Existing NH-based precursors often decompose at low temperatures, limiting their application.
• There is a need for stable lead precursors for deposition techniques.

Purpose of the Study:

• To design, synthesize, and characterize a novel aliphatic NHPb.
• To investigate the thermal stability and decomposition pathways of the new compound.
• To evaluate its potential as a precursor for chemical vapor deposition (CVD) and atomic layer deposition (ALD).

Main Methods:

• Synthesis and isolation of rac-N ², N ³-di- tert-butylbutane-2,3-diamido lead(II) (1Pb).
• Structural characterization of the synthesized lead complex.
• Thermal decomposition analysis and vapor pressure measurements.

Main Results:

• A novel aliphatic NHPb, 1Pb, was successfully synthesized and isolated.
• 1Pb exhibits significantly enhanced thermal stability, decomposing above 150 °C, a substantial improvement over related compounds.
• The compound possesses a high vapor pressure (1 Torr at 94 °C), indicating suitability for deposition processes.

Conclusions:

• The bulky tert-butylamido groups and butane backbone effectively prevent redox decomposition.
• 1Pb is a highly stable Pb(II) complex with excellent volatility.
• This novel NH-based lead precursor is promising for the CVD and ALD of lead-containing functional materials.