Design and Synthesis of the First Spiro Bis(isoxazoline) Derivatives as Asymmetric Ligands

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All calculations were performed using the teXsan crystallographic software package of Molecular Structure Corporation, b = 10.154(2) Å, c = 10.865(3) Å

HPLC conditions: 4 (EtOH 3.0 mL/min, 21 min, 29 min)

Enantiomeric excess was determined by13C NMR spectroscopy after derivatization with 1,2-diphenylethylenediamine. Alexakis, A.; Frutos, J. C.; Mangeney, P.Tetrahedron:  Asymmetry1993,4, 2431−2434.

Crystal, 2023, monoclinic