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Synthesis 2005(7): 1148-1156
DOI: 10.1055/s-2005-861856
DOI: 10.1055/s-2005-861856
PAPER
© Georg Thieme Verlag Stuttgart · New York
Synthesis of Isoaminile Mediated by Enzymes
Further Information
Received
11 August 2004
Publication Date:
10 March 2005 (online)
Publication History
Publication Date:
10 March 2005 (online)
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.
Key words
drugs - enzymes - enantiomeric resolutions - rearrangements - lactones
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