The Domino Oxa-Michael-Aldol-Reaction Reinvestigated: A New P-Based Organocatalyst for Xanthenone Scaffolds

Abstract

The oxa-Michael-aldol condensation reaction offers a fast access to xanthenone scaffolds, which are an important structural motif in natural products. This reaction was investigated and a new organocatalyst based on phosphine was discovered (PhPMe₂). After optimization of the reaction conditions, the Michael donors and acceptors were screened to determine the scope and limitations of this reaction. Furthermore, important observations were made, allowing the formulation of a surprising reaction pathway for this catalyst system.

Key words

organocatalyst - domino oxa-Michael-aldol - phosphine - heterocycles - xanthenones

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