Tetrahedron

Regiospecific α-substitution of crotonic esters synthesis of naturally occurring derivatives of 6-ethyljuglone

B Caron, P Brassard

Index: Caron, Brigitte; Brassard, Paul Tetrahedron, 1991 , vol. 47, # 25 p. 4287 - 4298

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Citation Number: 10

Abstract

Methyl β-methoxycrotonate is alkylated regiospecifically, through the anion, in the α-position. Enolsilylation of the resulting β, γ-unsaturated ester affords the corresponding 1, 1, 2, 3- tetrasubstituted butadiene. Cycloaddition of the latter to the appropriate halogenated benzoquinone, followed by various transformations, provides the first recorded syntheses of several natural products derived from 6-ethyl-7-methoxyjuglone.