Mechanistic Dichotomy in the Asymmetric Allylation of Aldehydes with Allyltrichlorosilanes Catalyzed by Chiral Pyridine N-Oxides
Journal article, 2013

Detailed kinetic and computational investigation of the enantio- and diastereoselective allylation of aldehydes 1 with allyltrichlorosilanes 5, employing the pyridine N-oxides METHOX (9) and QUINOX (10) as chiral organocatalysts, indicate that the reaction can proceed through a dissociative (cationic) or associative (neutral) mechanism: METHOX apparently favors a pentacoordinate cationic transition state, while the less sterically demanding QUINOX is likely to operate via a hexacoordinate neutral complex. In both pathways, only one molecule of the catalyst is involved in the rate- and selectivity-determining step, which is supported by both experimental and computational data.

organocatalysis

allylsilanes

pyridine N-oxides

allylation

calculations

Author

Andrei V. Malkov

University of Glasgow

Loughborough University

Sigitas Stoncius

Vilnius University

University of Glasgow

Mark Bell

University of Dundee

University of Glasgow

Fabiomassimo Castelluzzo

University of Glasgow

Bayer SpA, Italy

Pedro Ramirez-Lopez

University of Seville

University of Glasgow

Lada Biedermannova

University of Glasgow

Czech Academy of Sciences

Vratislav Langer

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Lubomir Rulisek

Czech Academy of Sciences

Pavel Kocovsky

Stockholm University

University of Glasgow

Chemistry - A European Journal

0947-6539 (ISSN) 1521-3765 (eISSN)

Vol. 19 28 9167-9185

Subject Categories

Chemical Sciences

DOI

10.1002/chem.201203817

More information

Latest update

11/12/2021