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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
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Azobenzenyl Calcium Complex: Synthesis and Reactivity Studies of a Ca(I) Synthon
Yumiao Liu1, Kang Zhu1, Liang Chen1
1College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
Inorganic Chemistry
|December 8, 2022
Summary
Researchers explored low-valent calcium chemistry, creating a novel calcium(I) synthon. This potent electron donor, an azobenzenyl calcium complex, reacts with various reagents to form new calcium compounds.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Calcium Chemistry
Background:
- Low-valent calcium complexes are challenging to synthesize and characterize.
- Understanding their reactivity is crucial for developing new synthetic methodologies.
Purpose of the Study:
- To synthesize and characterize a low-valent calcium(I) complex.
- To investigate the reactivity of this calcium(I) synthon with various electrophiles and substrates.
Main Methods:
- Reduction of a calcium iodide precursor ([LCaI(THF)]2) using KC8.
- Isolation and characterization of resulting calcium complexes using spectroscopy (EPR, UV-vis) and X-ray crystallography.
- Density-functional theory (DFT) studies to elucidate reaction mechanisms.
Main Results:
- Successful synthesis of a dinuclear calcium azaallyl complex and an azobenzenyl calcium complex.
- Characterization of the azobenzenyl moiety as a radical anion, acting as a potent one-electron donor.
- Demonstration of the azobenzenyl calcium complex's reactivity with azides, carbenes, carbon disulfide, tungsten hexacarbonyl, sulfur, and silver bromide, yielding diverse new calcium complexes.
Conclusions:
- The azobenzenyl calcium complex serves as a versatile low-valent calcium(I) synthon.
- This study expands the scope of low-valent calcium chemistry and provides insights into its reactivity.
- The findings highlight the potential of radical anions in stabilizing and mediating reactions of low-valent main group elements.
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