Comparative Diels−Alder Reactivities within a Family of Valence Bond Isomers: A Biomimetic Total Synthesis of (±)-UCS1025A
作者:Thomas R. Hoye、Vadims Dvornikovs
DOI:10.1021/ja0581999
日期:2006.3.1
intramolecular silyl triflate-induced cyclization of an in situ-generated silyl ketene acetal onto an imide carbonyl group (e.g., 7 to 8) was developed. The IMDA relative reactivities of a family of valencebondisomers, each differing in the precise nature of the dienophilic subunit, were determined. Under biologically relevant conditions (D2O, pH 7.2 buffer, ca. 25 degrees C), triene 2, via its lactone ring-opened
作者:Barry Lygo、Mohamed Bhatia、Jason W.B. Cooke、David J. Hirst
DOI:10.1016/s0040-4039(03)00288-0
日期:2003.3
In this paper we report the development of a stereoselective IMDA approach to the phytotoxic polyketides (+/-)-solanapyrones A and B. The stereoselectivity of the key IMDA cycloaddition was optimized by investigating a range of 2,8,10-dodecatrienoic acid derivatives. This established that use of the Weinreb amide led to the desired exo-selectivity and also facilitated construction of the pyrone moiety. A novel approach to the installation of the C-3 formyl group in solanapyrone A is also described. (C) 2003 Elsevier Science Ltd. All rights reserved.
IMDA Reactions of β,δ-Diketoester-Substituted 1,7,9-Undecatrienes: Application in the Formal Synthesis of Solanapyrone D
作者:Barry Lygo、David J. Hirst
DOI:10.1055/s-2005-918445
日期:——
In this paper we describe the synthesis of β,δ-diketoester substituted 1,7,9-undecatrienes and their intramolecular Diels-Alder (IMDA) cycloadditions under thermal and acid-catalysed conditions. Application of this chemistry in the synthesis of a solanapyrone D precursor is reported.