The Chemistry of Coumarin Derivatives. Part 5. Unusual course of the reaction of 4-hydroxycoumarin and aliphatic aldehydes

Authors

  • Giovanni Appendino,

    Corresponding author
    1. Dipartimento di Scienza e Tecnologia del Farmaco, via Giuria 9, I–10125 Torino
    • Dipartimento di Scienza e Tecnologia del Farmaco, via Giuria 9, I–10125 Torino
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  • Giancarlo Cravotto,

    1. Dipartimento di Scienza e Tecnologia del Farmaco, via Giuria 9, I–10125 Torino
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  • Gian Mario Nano,

    1. Dipartimento di Scienza e Tecnologia del Farmaco, via Giuria 9, I–10125 Torino
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  • Giovanni Palmisano,

    Corresponding author
    1. Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, via Venezian 21, 1–20133 Milano
    • Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, via Venezian 21, 1–20133 Milano
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    • Centro Studio per le Sostanze Organiche Naturali del CNR, via Venezian 21, I–20133 Milano.

  • Rita Annunziata

    1. Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, via Venezian 21, 1–20133 Milano
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  • Part 4: [1].

Abstract

The reaction of 4-hydroxycoumarin and certain aliphatic aldehydes affords 1:1 or complex 2:2 adducts besides (or in place) of the expected 2:1 bis(coumarin) adducts. Reaction with heptanal, cyclohexanecarbaldehyde, and pivalaldehyde are reported as representative. The structure of the reaction products was established by spectroscopical techniques, including X-ray analysis, and their formation was mechanistically rationalized. Some of the 1:1 adducts are synthetically useful for the preparation of 3-alkyl-4-hydroxycoumarins.

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