Stereoselective Syntheses of Masked β-Amino Acid Containing Phthalides.

Helv Chim Acta

Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstr. 69, AT-4040 Linz, Austria.

Published: November 2022

We herein report a protocol for the asymmetric aldol-initiated cascade addition of isoxazolidin-5-ones to -cyanobenzaldehydes by using 's bifunctional organocatalyst. This approach allows for the synthesis of various novel β-amino acid-phthalide conjugates with good enantio- and diastereoselectivities in reasonable yields and the further ring-opening of these compounds to acyclic carboxylic acid derivatives was demonstrated too.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7614226PMC
http://dx.doi.org/10.1002/hlca.202200110DOI Listing

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