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A New Type of Stereoselectivity in Baeyer–Villiger Reactions: Access to E ‐ and Z ‐Olefins
Author(s) -
Zhang ZhiGang,
Roiban GheorgheDoru,
Acevedo Juan Pablo,
Polyak Iakov,
Reetz Manfred T.
Publication year - 2013
Publication title -
advanced synthesis and catalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.541
H-Index - 155
eISSN - 1615-4169
pISSN - 1615-4150
DOI - 10.1002/adsc.201200759
Subject(s) - chemistry , cyclohexanone , stereoselectivity , moiety , catalysis , stereochemistry , baeyer–villiger oxidation , ketone , selectivity , organic chemistry
A new concept for accessing configurationally defined trisubstituted olefins has been developed. Starting from a common ketone precursor of the type 4‐ethylidenecyclohexanone, Baeyer–Villiger monooxygenases are employed as catalysts in diastereoselective Baeyer–Villiger reactions leading to the corresponding E ‐ or Z ‐configurated lactones. Wild‐type cyclohexanone monooxygenase (CHMO) as catalyst delivers the E ‐isomers and a directed evolution mutant the opposite Z ‐isomers. Subsequent transition metal‐catalyzed chemical transformations of a key product containing a vinyl bromide moiety provide a variety of different trisubstituted E‐ or Z‐ olefins. A model based on QM/MM sheds light on the origin of this unusual type of diastereoselectivity. In contrast to this biocatalytic approach, traditional Baeyer–Villiger reagents such as m ‐CPBA fail to show any selectivity, 1:1 mixtures of E ‐ and Z ‐olefins being formed.