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Syntheses and characterizations of linear triborazanes
William C Ewing1, Patrick J Carroll, Larry G Sneddon
1Department of Chemistry, University of Pennsylvania , Philadelphia, Pennsylvania 19104-6323, United States.
Inorganic Chemistry
|August 28, 2013
Summary
New linear aminoborane anions and triborazanes were synthesized from amine boranes. These compounds exhibit stability up to 90 °C and undergo selective chlorination reactions.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
Background:
- Amine boranes are versatile precursors in boron chemistry.
- The synthesis of novel boron-nitrogen compounds is crucial for developing new materials and catalysts.
Purpose of the Study:
- To synthesize and characterize novel linear aminoborane anions and triborazanes.
- To investigate the thermal stability and reactivity of these new boron-nitrogen compounds.
Main Methods:
- Reaction of amine boranes with sodium hexamethyldisilazane to form aminoborane anions.
- Subsequent reactions of these anions with ammonium chloride or pyridine hydrochloride.
- Crystallographic confirmation of the triborazane structure.
- Thermal stability studies and chlorination reactions.
Main Results:
- Synthesis of five-membered, linear aminoborane anions (Na(+)[BH3N(R)HBH2N(R)HBH3(-)]) for R = H, Me, and benzyl.
- Formation of linear triborazanes (BH3(RNHBH2)2N(R)H2) and pyridine-capped aminoboranes.
- Triborazanes showed stability up to 90 °C.
- Selective mono- and dichlorination of triborazanes at the terminal boron atom.
Conclusions:
- Novel linear aminoborane anions and triborazanes were successfully synthesized.
- The synthesized compounds display moderate thermal stability and undergo controlled chlorination.
- This work expands the scope of boron-nitrogen chemistry and offers potential for further functionalization.
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