Direct Conversion of Activated 5-Hydroxymethylfurfural into δ-Lactone-Fused Cyclopentenones

Valorization of biomass derived feedstock (e.g., 5-hydroxymethylfurfural platform) is a very active field of chemical research. In this study, 5-hydroxymethylfurfural is converted into cyclopenten-2-ones by virtue of furfural's activation and Meldrum's acid's tendency to undergo decomposition/esterification. Experimental and computational studies suggest a domino rearrangement-lactonization reaction involving BINOL-catalyzed lactonization as the rate-determining step. The novel lactone-fused cyclopenten-2-ones, which bear a quaternary carbon and resemble a didemnenone natural product structure, are converted into several derivatives with potential interest for the fields of synthetic and medicinal chemistry.

Development and application of chiral spirocyclic phosphoric acids in asymmetric catalysis

This review describes the synthetic methods for the preparation of chiral spirocyclic phosphoric acids (SPAs), and their dynamically developing application for catalytic enantioselective transformations.