2025/01/01 by Alastair J. Nimmo, Alister S. Goodfellow, Jacob T. Guntley +4 · 1 voice · 1 citation
Chemistry · #Asymmetric Synthesis and Catalysis #Axial and Atropisomeric Chirality Synthesis #Molecular spectroscopy and chirality
paper · pdf · doi:10.1039/d5sc02435h
openalex publication_date 2025/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/08
-aryl substituents giving atropisomeric products, leading to an effective process for iminothia- and iminoselenazinanones heterocyclic products containing both point and axially chiral stereogenic elements with excellent stereocontrol (up to >95 : 5 dr and 98 : 2 er). Mechanistic investigation showed that (i) the catalytically liberated aryloxide could deprotonate an electron-deficient thiourea; (ii) in the absence of an isothiourea catalyst, this leads to formation of racemic product; (iii) a crossover experiment indicates the reversibility of the thia-Michael addition. Computational analysis has identified the factors leading to enantioselectivity within this process, with stereocontrol arising from the lactamisation step within the catalytic cycle.