Multi-Talented Bismuthinidenes: Double C(sp³)─I Bond Activation Using Single or Two Bi Centers

Area of Science:

• Organometallic Chemistry
• Main group chemistry
• Bismuth chemistry

Background:

• Organobismuth compounds are gaining interest due to their unique reactivity.
• Exploring the reactivity of low-valent bismuth complexes with organic halides is crucial for synthetic applications.

Purpose of the Study:

• To investigate the reactivity of low-valent bismuth complexes with bulky substituents towards dihaloalkanes.
• To elucidate the influence of steric bulk and reaction stoichiometry on the C-I bond activation pathways.

Main Methods:

• Synthesis and characterization of organobismuth complexes.
• Reactions of bismuth complexes with diiodomethane and dihaloethanes.
• Stoichiometric control and product isolation.

Main Results:

• The bismuth complex [2,6-(DippN=CH)2C6H3]Bi (1Dipp) undergoes double C-I bond activation with CH2I2.
• The tert-butyl analogue [2,6-(tBuN=CH)2C6H3]Bi (1tBu) shows stoichiometry-dependent reactivity with CH2I2, yielding dinuclear or mononuclear products.
• Reactions with CH2ClX result in the formation of [2,6-(tBuN=CH)2C6H3]Bi(CH2Cl)X.

Conclusions:

• Low-valent bismuth complexes with bulky substituents exhibit diverse reactivity towards dihaloalkanes.
• Stoichiometry plays a critical role in directing the reaction pathway and product distribution.
• These findings expand the synthetic utility of organobismuth compounds.