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Calcium Alkynyl(hydrido)zincates
Marcos López-Aguilar1,2, Kyle G Pearce1, Michael S Hill1
1Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
Organometallics
|July 30, 2026
Summary
This study details the synthesis of novel calcium-zinc acetylide complexes using β-diketiminato calcium hydride and terminal alkynes. The reactions yield diverse structures, including dialkynyl- and tetrakis-(alkynyl)-zincates, with unexpected toluene activation observed in one case.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Main Group Chemistry
Background:
- Calcium and zinc complexes are important in catalysis and materials science.
- β-Diketiminato ligands offer steric protection and electronic tunability for metal centers.
- Heterobimetallic complexes can exhibit unique reactivity due to cooperative effects.
Purpose of the Study:
- To synthesize and characterize novel heterobimetallic calcium-zinc acetylide derivatives.
- To explore the reactivity of β-diketiminato calcium hydride dimers with zinc complexes and alkynes.
- To investigate the influence of alkyne stoichiometry on the resulting product structures.
Main Methods:
- Reaction of [(BDI)-CaH]2 dimer with [ZnTMP2] in the presence of terminal alkynes.
- Characterization of products using spectroscopic methods and X-ray crystallography.
- Controlled variation of alkyne equivalents to study ligand substitution patterns.
Main Results:
- Synthesis of dialkynyl-(hydrido)-zincates and tetrakis-(alkynyl)-zincates with diverse structures.
- Observation of ligand redistribution leading to β-diketiminato calcium acetylides.
- Unexpected toluene activation and formation of a new complex [(THF)2Ca-(μ-C≡CPh)3Zn-(CH2Ph)]2 under specific conditions.
Conclusions:
- The reaction conditions, particularly alkyne stoichiometry, significantly influence the structure of calcium-zinc acetylide derivatives.
- The observed toluene activation highlights the potential for C-H bond functionalization in these systems.
- This work expands the scope of accessible heterobimetallic calcium-zinc compounds and their reactivity.
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