Synthesis 2005(7): 1148-1156  
DOI: 10.1055/s-2005-861856
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Isoaminile Mediated by Enzymes

Fabrizio Antonietti, Elisabetta Brenna, Claudio Fuganti, Francesco G. Gatti*, Tommaso Giovenzana, Valentina Grande, Luciana Malpezzi
Dipartimento di Chimica dei Materiali ed Ingegneria Chimica ‘G. Natta’ del Politecnico, Centro CNR per la Chimica delle sostanze Naturali, Via Mancinelli 7, 20131 Milano, Italy
Fax: +39(02)23993082; e-Mail: Francesco.Gatti@polimi.it;
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Publikationsverlauf

Received 11 August 2004
Publikationsdatum:
10. März 2005 (eFirst)

Abstract

A lipase-mediated synthesis of all four enantiomers of isoaminile is reported. The key issues of the paper are: (i) enantioselective acetylation of allylic alcohol (E)-(±)-5 to give (E,S)-5 (ee = 92%) and (E,R)-6 (ee >99%); (ii) Claisen-Johnson rearrangement of R and S enantiomers of 5 to generate the quaternary benzylic stereocenter; (iii) chromatographic separation of aldehyde diastereo­isomers; (iv) X-ray structure of aldehyde (2R,4R)-10; (v) unpredicted formation of lactone 12 during the hydrolysis of 11.

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