Jiang R,
Ding L,
Zhang C,
You S.-L.
*
Shanghai Institute of Organic Chemistry, P. R. of China
Iridium-Catalyzed
Z-Retentive Asymmetric Allylic Substitution Reactions.
Science 2021;
371: 380-386
Key words
iridium catalysis - enantioselectivity -
Z-selectivity
Significance
The You group reports two unique methods for enantioselective iridium-catalyzed allylic substitution reactions, which are highly selective for the thermodynamically less stable Z-alkene products. Conventionally, metal-catalyzed asymmetric allylic substitution reactions favor the E-isomer of the products.
Comment
The authors rationalized their reaction design by focusing on developing a catalytic system that allowed for a slow isomerization from the initial anti-π-allyl complex to the more favored syn-π-allyl species. Subsequent capture of the chiral anti-π-iridium species by a nucleophile selectively generated the enantioenriched Z-alkene products.
