Publication 51 de l'année 2018

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  1. Primary Anion-π Catalysis and Autocatalysis
    Zhang, X.; Hao, X.; Liu, L.; Pham, A.-T.; López-Andarias, J.; Frontera, A.; Sakai, N.; Matile, S.
    J. Am. Chem. Soc. 2018, 140, 17867-17871

Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion−π interactions account for function. Rate enhancements maximize at 270 for anion−π catalysis on fullerenes and at 5100 M–1 for autocatalysis. The occurrence of anion−π autocatalysis is confirmed with increasing initial rates in the presence of additional product. Computational studies on autocatalysis reveal transition state and product forming a hydrogen-bonded noncovalent macrocycle, like holding their hands and dancing on the active π surface, with epoxide opening and nucleophile being activated by anion−π interactions and hydrogen bonds to the product, respectively.

DOI : 10.1021/jacs.8b11788 

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