Premium
Asymmetric Anion–π Catalysis on Perylenediimides
Author(s) -
Wang Chao,
Miros François N.,
Mareda Jiri,
Sakai Naomi,
Matile Stefan
Publication year - 2016
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201608842
Subject(s) - chemistry , catalysis , quadrupole , ion , enamine , transition state , photochemistry , inorganic chemistry , computational chemistry , crystallography , organic chemistry , physics , atomic physics
Anion–π catalysis, that is the stabilization of anionic transition states on π‐acidic aromatic surfaces, has so far been developed with naphthalenediimides (NDIs). This report introduces perylenediimides (PDIs) to anion–π catalysis. The quadrupole moment of PDIs (+23.2 B) is found to exceed that of NDIs and reach new records with acceptors in the core (+70.9 B), and their larger surface provides space to better accommodate chemical transformations. Unlike NDIs, the activity of PDI catalysts for enolate and enamine addition is determined by the twist of their π surface rather than their reducibility. These results, further strengthened by nitrate inhibition and circular dichroism spectroscopy, support an understanding of anion–π interactions centered around quadrupole moments, i.e., electrostatic contributions, rather than redox potentials and charge transfer. The large PDI surfaces provide access to the highest enantioselectivities observed so far in anion–π catalysis (96 % ee ).