The zirconium-catalyzed asymmetric carbo-alumination reaction (or ZACA reaction) was developed by Nobel laureate
Ei-ichi Negishi.
It facilitates the chiral functionalization of alkenes using organoaluminium compounds under the influence of chiral bis-indenylzirconium catalysts (e.g. bearing chiral
terpene residues,
as in (+)- or (−)-bis
1-neomenthyl)indenylirconium dichloride
). In a first step the alkene inserts into an Al-C bond of the reagent, forming a new chiral
organoaluminium
Organoaluminium chemistry is the study of compounds containing bonds between carbon and aluminium. It is one of the major themes within organometallic chemistry. Illustrative organoaluminium compounds are the dimer trimethylaluminium, the monomer ...
compound in which the aluminium atom occupies the lesser hindered position. This intermediate is usually oxidized by oxygen to form the corresponding chiral alcohol (cf.
hydroboration–oxidation reaction). The reaction can also be applied to dienes, where the least sterically hindered double bond is attacked selectively.
See also
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Organoaluminium chemistry
Organoaluminium chemistry is the study of compounds containing bonds between carbon and aluminium. It is one of the major themes within organometallic chemistry. Illustrative organoaluminium compounds are the dimer trimethylaluminium, the monomer ...
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Organozirconium chemistry
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Indenyl effect In organometallic chemistry, a transition metal indenyl complex is a coordination compound that contains one or more indenyl ligands. The indenyl ligand is formally the anion derived from deprotonation of indene. The η5-indenyl ligand is relate ...
References
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Organometallic chemistry