The chemistry of coumarin derivatives, part 2. Reaction of 4??hydroxycoumarin with α, β??unsaturated aldehydes

G Appendino, G Cravotto, S Tagliapietra…

Index: Appendino; Cravotto; Tagliapietra; Nano; Palmisano Helvetica Chimica Acta, 1990 , vol. 73, # 7 p. 1865 - 1878

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Citation Number: 37

Abstract

Abstract 4-Hydroxycoumarin (= 4-hydroxy-2H-1-benzopyran-2-one) reacts with enals to give 1, 2-or 1, 4-addition products, depending on the nature and relative location of the substituents on the olefinic double bond (Scheme 2). The resulting adducts further react intra- or intermolecularly, affording dimeric coumarins or pyranocoumarins in the case of 1, 2- addition and acetalic pyranocoumarins in the case of 1, 4-addition. With enals bearing ...