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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)
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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
- 1
Stümer W, andFunke S. inventors; U.S. Patent, 2934557. (Kali-Chemi), -
2a For examples, see:
Brenna E.Carraccia N.Fuganti C.Fuganti D.Grasselli P. Tetrahedron: Asymmetry 1997, 8: 3801 -
2b
Brenna E.Fuganti C.Grasselli P.Serra S. Eur. J. Org. Chem. 2001, 1349 -
2c
Brenna E.Fuganti C.Gatti FG.Passoni M.Serra S. Tetrahedron: Asymmetry 2003, 8: 2401 -
2d
Brenna E.Dei Negri C.Fuganti C.Gatti FG.Serra S. Tetrahedron: Asymmetry 2004, 15: 335 -
2e
Abate A.Brenna E.Fronza G.Fuganti C.Gatti FG.Serra S.Zardoni E. Helv. Chim. Acta 2004, 87: 765 - For recent examples illustrating the preparation of quaternary benzyl stereocentres, see:
-
3a
Comprehensive Asymmetric Catalysis
Jacobsen EN.Pfaltz A.Yamamoto H. Springer; Heidelberg, Germany: 1999. -
3b
Hayashi T. Synlett 2001, 879 -
3c
Takaya Y.Ogasawara M.Hayashi T.Sakai M.Miyaura N. J. Am. Chem. Soc. 1998, 120: 5579 -
3d
Takaya Y.Ogasawara M.Hayashi T. Tetrahedron Lett. 1998, 39: 8479 -
3e
Magnus M.Magnus P. Nature (London) 1997, 385: 799 -
3f
Myers AG.Yang BH.Chen H.McKistry L.Kopecky DJ.Gleason JL. J. Am. Chem. Soc. 1997, 119: 6496 -
3g
Pippel DJ.Curtis MD.Du H.Beak P. J. Org. Chem. 1998, 63: 2 -
3h
Geller T.Schmalz HG.Bats J. Tetrahedron Lett. 1998, 39: 1537 -
3i
Hoppe D.Hense T. Angew. Chem., Int. Ed. Engl. 1997, 36: 2283 - 4 The ketone 2 was prepared by addition of i-PrMgBr to benzonitrile, following the procedure for the preparation of butyrophenone:
Gilman H.Eisch J. J. Am. Chem. Soc. 1957, 79: 2150 - 5
Budram RS.Palaniswamy VA.Eisenbraun EJ. J. Org. Chem. 1986, 51: 1402 - 6
Flack HD. Acta Crystallogr., Sect. A: Found. Crystallogr. 1983, 39: 876 - 7
Sheldrick GM. SHELXL97 University of Göttingen; Germany: 1997. - 8
Tiecco M.Testaferri L.Tingoli M.Bartoli D. Tetrahedron 1990, 46: 7139