Formation and [4+ 2] cycloaddition reactions of 2, 3??dimethylene??2, 3??dihydrothiophene

KJ van den Berg, AM van Leusen

Index: Berg, Keimpe J. van den; Leusen, Albert M. van Recueil des Travaux Chimiques des Pays-Bas, 1993 , vol. 112, # 1 p. 7 - 14

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Citation Number: 8

Abstract

Abstract 2, 3-Dimethylene-2, 3-dihydrothiophene (1), the thiophene analog of o-xylylene (o- quinodimethane), was generated in situ from the (trialkylammoniomethyl)- (trimethylsilylmethyl) thiophene iodides 4 or 5 by fluoride-induced 1, 4 climination, and was trapped by [4+ 2] cycloadditions with a series of dienophiles. The reaction of 1 with dimethyl fumarate was considerably faster than with dimethyl maleate. Unsymmetrical dienophiles ...