A Cyclic (Alkyl)(boryl)germylene Derived from a Cyclic (Alkyl)(amino)germylene
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Nanyang Link 21, Singapore, 637371, Singapore.
Angewandte Chemie (International Ed. in English)
|October 10, 2019
Summary
A novel ring expansion reaction forms a six-membered dibromogermane. Subsequent reduction and Lewis base adduct formation yield cyclic borylgermylenes, important in organometallic chemistry.
Area of Science:
- Organometallic Chemistry
- Boron and Germanium Chemistry
- Synthetic Inorganic Chemistry
Background:
- Cyclic germylenes are versatile intermediates in inorganic synthesis.
- Boron halides are reactive electrophiles used in functionalization reactions.
Purpose of the Study:
- To explore the reactivity of cyclic (alkyl)(amino)germylenes with dibromomesitylborane.
- To synthesize novel cyclic (alkyl)(boryl)germylene-Lewis base adducts.
- To investigate the subsequent reactions of these adducts.
Main Methods:
- Ring expansion reaction of a cyclic germylene with MesBBr2.
- Reduction of dibromogermane derivatives using potassium graphite (KC8).
- Formation of Lewis base adducts with phosphines (PMe3) and N-heterocyclic carbenes (NHC).
Main Results:
- A six-membered dibromogermane derivative was successfully synthesized.
- Cyclic (alkyl)(boryl)germylene-Lewis base adducts were obtained via reduction and complexation.
- The PMe3 adduct reacted with H2 to form a germane, likely through a base-free germylene intermediate.
Conclusions:
- The study demonstrates a new route to functionalized germanes and germylenes.
- The formation of borylgermylene adducts expands the scope of germylene chemistry.
- The reaction with H2 suggests potential catalytic applications for these novel compounds.
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