cheminform abstract: straightforward strategy for the stereoselective synthesis of spiro-fused...
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Quinoline derivativesR 0410 Straightforward Strategy for the Stereoselective Synthesis of Spiro-Fused
(C-5)Isoxazolino- or (C-3)Pyrazolino-(C-3)quinolin-2-ones from Baylis—Hillman Adducts by 1,3-Dipolar Cycloaddition and Reductive Cyclization. — A general two-step approach to the synthesis of spirocyclic isoxazolino- and pyrazolinoquinolin-ones includes a 1,3-dipolar cycloaddition of Baylis—Hillman adducts with nitrile ox-ides or nitrile imines, followed by reductive cyclization. The cycloaddition step pro-ceeds with excellent diastereoselectivity. Spirocyclic pyrazolinopyridinones (XVI) are obtained on a similar way. In contrast, the Baylis—Hillman adducts obtained from methyl vinyl ketone [cf. (XI)] are no suitable substrates as oximes (XIII) are formed instead. — (SINGH, V.; SINGH, V.; BATRA*, S.; Eur. J. Org. Chem. 2008, 32, 5446-5460; Div. Med. Process Chem., Cent. Drug Res. Inst., Lucknow 226 001, India; Eng.) — Mischke
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ChemInform 2009, 40, issue 11 © 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cheminform.wiley-vch.de
ChemInform 2009, 40, issue 11 © 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim